According to Newzoo's data, 41% of 70M Xbox 360 gamers in the US and Western Europe use a tablet; 61% of them use an iPad. This means that over 29M gamers would benefit from being able to use their tablets with the 360 - and that does not include gamers who would be able to enjoy functionality from a mobile device like Android or iPhone. 52% of Xbox 360 users also enjoy gaming on smartphones.
PlayStation 3 users also heavily use tablets, with 40% of the PS3 populace owning a tablet, while 57% of them play smartphone games as well. The PlayStation Vita already can be used as a second screen for the PS3, but with poor Vita sales, perhaps Sony should have left that functionality to third party console manufacturers.
Microsoft showed off the Smartglass feature at E3 2012 during its E3 2012 press conference. Check out the video to see just how the new feature will work.