77% of the UK online population are active participants

"Like the population itself, the picture is nuanced but six striking themes emerged:
The model which has guided many people's thinking in this area, the 1/9/90 rule, is outmoded. The number of people participating online is significantly higher than 10%.
Participation is now the rule rather than the exception: 77% of the UK online population is now active in some way.
This has been driven by the rise of 'easy participation': activities which may have once required great effort but now are relatively easy, expected and every day. 60% of the UK online population now participates in this way, from sharing photos to starting a discussion.
Despite participation becoming relatively 'easy', almost a quarter of people (23%) remain passive - they do not participate at all.
Passivity is not as rooted in digital literacy as traditional wisdom may have suggested. 11% of the people who are passive online today are early adopters. They have the access and the ability but are choosing not to participate.
Digital participation now is best characterised through the lens of choice. These are the decisions we take about whether, when, with whom and around what, we will participate. Because participation is now much more about who we are, than what we have, or our digital skill."

Source:  Data from BBC Future Media, reported in a blog post, 4th May 2012

Note:  "The Participation Choice is a synthesis of primary and secondary research conducted over the past 18 months. The data published today are all taken from the most recent, large scale survey of 7,500 UK adults - representative of the UK online population."

Instagram has 40 million users

"Instagram received a fair amount of press over the last week. First, 10 days ago, the app launched on Android. Then news of Facebook buying the tiny startup for $1 billion was everywhere from the Drudge Report to The Daily Show. The attention resulted in explosive growth. Since the launch of its Android app, Instagram’s user base grew from 30 to 40 million. That’s over 1,000,000 new users a day.
Rakshith, the creator of gramfeed, pinged us this morning after noticing the milestone from Instagram’s API. The 40 millionth user is valentinoelbuti. It seems at the time of this post’s writing, Instagram has exactly 40,026,379 users — or rather, roughly 5% of Facebook’s active user base."

Source:  TechCrunch, 13th April 2012

Facebook acquired Instagram for $1 billion

"Facebook has just announced that it will acquire Instagram, the popular mobile photo-sharing service, for $1 billion in cash and shares.
The social networking giant posted on the acquisition, its biggest yet, on its site, as well as on CEO and co-founder Mark Zuckerberg’s Timeline on Facebook.
Photos are critically important for Facebook, which has been slow to innovate in the fast-growing mobile arena in the important consumer space. By contrast, Instagram has taken the arena by storm, with its delightful and elegant app and the motto, “Fast beautiful photo sharing.”
Consumers have responded (including me — it is the only non-communications app I use many times a day). The San Francisco-based company — with only 13 employees — had 30 million Apple iPhone users before it came to Google’s Android last week, where it got more than a million new users in just 12 hours."

Source:  AllThingsD, 9th April 2012

1m Android versions of Instagram were downloaded in the first 24 hours

"Eager Android users awaiting the release of Instagram scooped up a million copies in less than 24 hours.
The free photo-sharing app made its official appearance on Google Play yesterday following a pre-registration period on March 24 that captured 430,000 interested users. Instagram CEO Kevin Systrom told The New York Times yesterday that the app was grabbing 2,000 people each minute following its debut."

Source:  CNET, 5th April 2012

Instagram has been downloaded 27m times

"Photo-sharing app Instagram has nearly doubled its total number of registered users since December, Instagram founder Kevin Systrom announced Sunday at the South by Southwest conference.
Instagram, which launched two years ago, now boasts 27 million registered users, up from 15 million in December of last year, according to Systrom. Foursquare, by comparison, claims just under 20 million users, and was founded in March of 2009."

Source:  Huffington Post, 11th March 2012

The most-followed brands on Pinterest

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Source:  DigiDay, 23rd February 2012
Note - this will be out of date very quickly, but it's a useful guide to the sorts of things that are popular at this stage.

The Instagram website gets 300m page views a month

"From day one, Instagram’s main priority has been building a great experience on its iPhone app — not on the web. But as it turns out, the photo-sharing service has become a huge web destination anyway: Instagram’s website is currently receiving 10 million page views each day, adding up to some 300 million page views per month, co-founder Kevin Systrom told GigaOM.
Such numbers would be impressive for any service, but they’re especially interesting given that the Instagram experience is so tailored to users of the app (currently available only on the iPhone), not viewers on the web."

Source:  GigaOM, 6th January 2012

Instagram has 13m users and 7 employees

"The popular photo app that’s responsible for flooding the internet with fuzzy, low-contrast, retro images of cats, hipsters and urban street scenes shows no sign of slowing down.
Of course we’re talking about Instagram and its iPhone-only app for sharing stylized photos. The startup attracted 12 million users in just over a year on the App Store. By early November, the small company — and we mean small; Instagram has just seven employees — grabbed another million and now boasts well over 13 million application users, co-founder Kevin Systrom shared with VentureBeat."

Source:  VentureBeat, 18th November 2011

Earlier - 10m users announced in September

There are over 200,000 LEGO videos on YouTube, and over 1m LEGO photos on Flickr

"The book is full color, hardcover, with 304 pages. There are 12 chapters that cover topics such as: The History of LEGO, Minifig Mania and LEGO Art.
I love some of the tidbits included in the text, such as the fact that there are over 200,000 LEGO videos on YouTube! Wow, who knew? Now I want to go waste hours watching them  Or what about the over 1 million photos that are tagged with LEGO on Flickr?"

Source:  From a review of the book Cult of LEGO, on the site The Gadgeteer, 24th October 2011

(Does anyone have a better source for the stats..?)

Instagram has 10m users

"Last October, we launched Instagram live in the App Store. Today, less than one year later, we’re happy to announce that the Instagram community now consists of over 10 million registered users.
As we prepare to celebrate our first year in the App Store, we’d like to extend our thanks to each and every one of the ten million folks who have taken the time to participate in Instagram by sharing small moments of life through gorgeous mobile photos."
Source:  Blog post by Instagram, 26th September 2011

Instagram has 9m users after only 11 months

"Instagram cofounder Kevin Systrom took the stage at TechCrunch Disrupt this morning. The photo sharing app was a pivot from a bigger idea, Burbn, and launched in the App Store last October.
The app has 9 million users -- it's almost as big as Foursquare in half the time. "

Source:  Business Insider, 13th September 2011

The growth of Flickr

Click to enlarge

"22 Oct 04: 1,000,000
20 Apr 05: 10,000,000
15 Feb 06: 100,000,000
22 Sep 06: 250,000,000
15 May 07: 500,000,000
19 Jul 07: 850,000,000
06 Oct 07: 1,500,000,000
13 Nov 07: 2,000,000,000
17 May 08: 2,500,000,000
03 Nov 08: 3,000,000,000
04 May 09: 3,500,000,000
11 Oct 09: 4,000,000,000
18 Sept 10: 5,000,000,000
1 Aug 11: 6,000,000,000"
Source:  Blog post on Kullin.net, 9th August 2011

The iPhone 4 is now the most popular camera on Flickr

"The iPhone 4 has an excellent camera; I’ve been using it as my primary point-and-shoot for a year now. It looks like I’m not alone either as the iPhone 4 has just taken the top slot for cameras on Flickr. More people now shoot pictures with an iPhone 4 than the top DSLR’s from Canon or Nikon.
The new list of top cameras on Flickr is as follows:
iPhone 4
Nikon D90
Canon EOS 5D Mark II
Canon EOS Digital Rebel XSi
Canon EOS REBEL T1i"
Source:  The Next Web, 21st June 2011

Instagram has 1.25m users per employee

"Yes, Instagram now has five million users. That’s 625,000 users for every month they’ve been in existence — with the growth accelerating. Just this past weekend they added 100,000 new users, for example. Even more amazing, there are now 1.25 million users for every one employee of Instagram.
I got a chance to catch up with Instagram co-founder Kevin Systrom this morning to talk about the milestone and the bigger picture for the service. Beyond the five million user mark (which they actually hit yesterday), Instagram is about to hit another huge milestone: 100 million photos. They’re at 95 million right now, and they’re adding roughly 860,000 a day. In other words, by the end of this week, the total number of pictures should cross 100 million.
For comparisons sake, it took Flickr two years to hit 100 million photos. Again, Instagram, just eight months. If you still had any doubts that a mobile photo revolution is happening, there you go.
As for the burgeoning Instagram ecosystem, Systrom says that there are now 2,500 unique apps out there accessing their APIs. Remarkably, they are also seeing some 350,000 connections across their API, meaning that some of the apps connected are massively popular. Which are the most popular? Webstagram and Flipboard were the top two the last time he looked, Systrom says. There are also now applications pushing photos into Instagram — not through the API, but through more creative means."
Source:  TechCrunch, 13th June 2011

Instagram has 4.25m registered users; 10 pictures are posted each second

"Here at TechCrunch Disrupt Instagram co-founder Kevin Systrom has just announced a new milestone for photo service Instagram, at 10 user photos posted per second, up from 6 photos per second officially announced couple of months ago.
“We’re like that growth we saw last time was really large, until we saw today,” said Systrom. When asked whether Tumblr founder David Karp had any advice for Kevin, “Kevin seems to be a few steps ahead of me.”
Systrom also revealed that Instagram currently has 4.25 million registered users after only seven months of existence. “It turns out if you make something that people want it spreads really well,” says Systrom. “People wanted to take pictures and have them shared across multiple networks all at once.”"

Source:  TechCrunch, 24th May 2011

One third of all items posted to Facebook are from mobile devices

"Some stats have been published, by researchers and the company themselves, about mobile usage of Facebook. But to content creators, one of the most important uses of the social network is when users create posts, sometimes posting original content, often sharing articles and media found elsewhere on the web. I was unable to find much data about how much of this activity occurs via mobile devices, so I decided to research my own.
I used a random sample set of more than 70,000 Facebook public posts (those from users with open privacy settings). The data includes status updates, videos, links and photos. 32.69% of those posts were created from mobile devices. The mobile Facebook website, m.facebook.com lead mobile usage with more than 18% of posts created through it."

Source:  Research by Dan Zarrella, posted onto his blog, 9th May 2011 

Instagram is growing at an estimated 130,000 users per week

"We sampled data from that API and loaded it into an RJMetrics Dashboard for analysis. This yielded detailed new insights into Instagram’s growth and user adoption.
Please note that these are estimates extracted from a sample set, so there may be a small margin of error (more details on our methods can be found at the end of the article). I provide a full breakdown below, but here are some highlights:
Instagram is currently adding 130,000 registered users per week
Instagram’s 2.2 million users upload 3.6 million new photos per week (or 6 photos per second)
37.5 percent of registered users have never uploaded a photo
5 percent of users have uploaded over 50 photos
65 percent follow nobody, and only 12 percent of users follow more than 10 people
For users who upload at least one photo, there is a 45 percent chance they will upload a photo the following week
Those same users have a 25 percent chance they will upload a photo 12 weeks later, representing a significantly stronger retention rate than Twitter."
Source:  Techcrunch, 10th March 2011

TripAdvisor has 45m reviews & opinions, and over 6m photos

"Milestones in the history of TripAdvisor:
- November 2000: http://www.tripadvisor.com goes live
- March 2002: The site is profitable
- April 2004: Sold to IAC
- August 2005: Part of Expedia, Inc.
- January 2005: The first hurdle of a million reviews and opinions is achieved.
- April 2008: 15 million reviews and opinions
- July 2009: 25 million reviews and opinions
- May 2010: 35 million reviews and opinions
- August 2010: TripAdvisor becomes the first travel site to have more than 40 million monthly users* to become the world's largest travel site.
- October 2010: 40 million reviews and opinions
- 2010: TripAdvisor launches 10 new sites around the world
- March 2011: 45 million reviews and opinions covering:
1) 85,000+ destinations
2) 474,000+ hotels
3) 100,000+ vacation rentals
4) 135,000+ attractions
5) 675,000+ restaurants
6) With 6,000,000+ candid traveller photos"
Source:  Press release from TripAdvisor, 12th April 2011
Note:  I'm not sure what constitutes an 'opinion' but I suspect it includes all comments on the forum

Facebook users uploaded 750m photos over the New Year weekend

"People celebrated New Year's on Facebook by uploading a record 750M photos over the weekend."
Source:  Tweet from Facebook, 4th January 2011

The most popular functions on US kids' mobile phones

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Source: Slide 17 of Four or More: The New Demographic, Pew Internet and American Life Project, 30th June 2010
The full presentation is well worth reading.