There were 800 million social media interactions around TV shows on the day they aired in the US in 2012

"The second annual Year End Stats Report from Trendrr includes data tracked via Twitter, public pages on Facebook and applications such as Get Glue and Viggle. For the year (period covers through November), Trendrr measured more than 800 million social interactions around TV programs on their day of air; taking into consideration all the chatter surrounding programs when off air, that number would reach into the billions, the social TV analytics company said.
An early look at the data reveals August as the most interactive month -- thanks to 17 days of the Summer Olympics on the networks of NBC -- but every month of 2012 drew at least double the number of social interactions than the same month in 2011.
Overall, the year saw a huge 800% growth of social TV chatter on Twitter, and it more than doubled on Facebook and in Apps.
For a second straight year, Nickelodeon's "SpongeBob SquarePants" was the entertainment program with the most social activity, accounting for nearly 25 million social interactions. Also high on the list were Fox's "The X Factor" (about 17 million), NBC's "The Voice" (11.5 million), USA's "WWE Raw" (11 million) and ABC Family's "Pretty Little Liars" (10.5 million), which holds the record for a single episode (1.52 million interactions for its mid-season finale)."

Source:  Data from Trendrr, reported by Variety, 26th December 2012

See the original Trendrr Infographic here

Note - I'm assuming that this is US only, given that no UK shows (or Japanese shows, or Brazillian shows...) appear in the figures

Foursquare users have checked in 3 billion times

"Foursquare has seen phenomenal growth over usage of its service. This week, it announced that it counted its 3 billionth check-in. Not bad for a service with just over 25 million users worldwide.
Two years ago, the location-based check-in service said it had experienced its biggest growth in history which was marked by more than 380 million check-ins, the Rally to Restore Sanity, and a single check-in from space. Now, 24 months later, the number of check-ins has increased exponentially — the company recorded its 1 billionth check-in September 2011, just 9 months later after its 380 millionth check-in.
Last September, the company stated that it had 2.5 billion check-ins counted. In that three month period, it averaged 167 million check-ins, or around 6.2 million per day. To get this number, TNW found the difference between November and September numbers and divided it by the days since (81) and that resulted in 6.2 million daily check-ins."

Source:  The Next Web, 21st November 2012

Earlier - 1.5 billion announced in February 2012

More than a million businesses use the Foursquare merchant platform

"Community: Over 25 million people worldwide
Over 2.5 billion check-ins, with millions more every day
Businesses: Over a million using the Merchant Platform (more information at foursquare.com/business)
Employees: Over 100 between headquarters in New York, an office in San Francisco, and a lovely outpost in London."

Source:  Data from Foursquare, 'updated September 2012', retrieved 5th October 2012

There were over 600,000 check ins at London 2012 Olympic venues on Facebook

This just in. 623,957 check ins to Olympic venues during the Olympic Games on Facebook. About 10% of that number on Foursquare.
— Alex Balfour (@AlexBalfour2012) September 2, 2012

Note - Alex Balfour is Head of New Media, London Olympic and Paralympic Games 2012

Foursquare's 15m users have checked in 1.5bn times

"Crowley said the 15 million global Foursquare users have checked in 1.5 billion times. With such a critical mass of data, the company is developing the ability to become the Amazon of locations: Serving up recommendations for places you would probably like to visit based on your profile and check-in history."

Source:  CNN Money, 29th February 2012

The top 10 shows on GetGlue had 10m checkins in 2011

"Today we're presenting full-year 2011 top 10 check-in data that the GetGlue team pulled together for us, revealing more than 6 million total check-ins for shows from "The Big Bang Theory" to "The Walking Dead." [...]
CBS's "The Big Bang Theory" dominated our weekly charts for much of the fall -- right from its two-episode season premiere, when it grabbed the No. 1 check-in spot in and topped the Nielsen ratings for its night (taking the No. 1 and No. 2 spots with its back-to-back fresh episodes). Throughout the fall it also got a big check-in boost thanks to being in syndication. No surprise that it takes the top spot in our full-year 2011 chart, with nearly 1.1 million check-ins.
Only two comedies -- "Big Bang Theory" and Fox's "Glee" -- land in our Top 10, unless you count the accidentally hilarious "American Horror Story" on FX.
No reality TV made the Top 10. How nice!
"There's not one drama here without a sci-fi or supernatural aspect to it," GetGlue CEO Alex Iskold points out. "And 'American Horror Story,' the only new show for 2011 to make the Top 10, is full of paranormal intrigue.""

Source:  Data from GetGlue reported in AdAge, 4th January 2012

Follow the link to see the full top 10

The three new-for-fall US TV shows with the highest number of GetGlue checkins got recommissioned

"Good news for three out of three of the new-this-fall shows that did make our cut: Fox's "New Girl" and FX's "American Horror Story" have been officially renewed by their networks, and "Once Upon a Time" has gotten a renewal of sorts too -- a full-season order from ABC that bodes well for a full second season. As I've noted before, social-TV popularity and Nielsen ratings are likely to never have an exactly linear correlation, but it's becoming more and more obvious that the shows social-media users are most passionate about have pretty good odds of not only surviving but becoming part of the pop-cultural conversation."

Source:  Analysis of GetGlue checkins in AdAge, 15th November 2011

Note - as it says, there's no direct linear relationship between checkins (or buzz) & viewing, but the shows that people make an effort to check in for are likely to be the ones that people enjoy most or feel most passionate about.