Last week Blizzard's Five-Year plan was leaked, which had a few super-duper golden nuggets of information including a next-generation MMO coming in 2013.
At the moment, Blizzard have a next-gen MMO coming in 2013 currently codenamed "Titan". Other tidbits of info included Diablo III released in Q4 2011, StarCraft II expansion and Phoenix campaign for Q4 2011 also, another StarCraft II expansion in Q1 2013 with Diablo III expansions in 2013 and 2014.
A World of Warcraft movie is listed and showing a release period of somewhere in Q4 2012, another WoW expansion ready for Q2 2012 and then yet another for Q4 2013.
The biggest nugget of info is obviously the next-gen codenamed MMO "Titan", which has a 2013 release date. Blizzard's Frank Pearce had a little to say about it at the VGAs:
"The media is not supposed to know anything about that, it's our next-gen MMO and we've only started talking about it in a limited fashion because we want to leverage the fact that we're working on something like that for the purpose of recruiting and getting some of the best talent in the industry on that project."