Haven't heard anything, but if there is going to be one it probably won't be for awhile. The DLC sales are still ringing in and they're gonna milk that cow. The new 'Genesis' release today suggests that they may not quite be done with ME2 DLC. We'll see
Genesis is not considered a piece of DLC that you would compare with say Arrival as it is simply a tool to make 5 choices from Mass Effect 1. It was bound to come out at some point and I see no reason for them to continue on with any new pieces of DLC,
especially no story based ones.
But as for a Game of the Year edition of Mass Effect 2, like Arkham said it won't be for a while if at all for the simple fact that Mass Effect 3 won't be coming out until the beginning of next year and I'm sure they want to give PS3 users ample time to playthrough
A lot of games with loads of story-driven DLC like Borderlands are usually major candidates for a GOTY edition that comes with the DLC's. However, I'm sure if they do actually make a GOTY edition, it will be after the last newest DLC has been out for a while,
and Arrival just recently came out.
I think that a "Collector's Edition" with all 3 games and DLC is more likely to appear instead. It'll probably cost a bundle, but I think that "Arkham City" will snag most of the GOTY honours this time around...:-)