I got to play this just a few moments ago at an IGN-sponsored booth here at CES in Vegas. I got an interview with one of the lead programmers and had a chance to enjoy the playable multiplayer demo they had available.
Unfortunately, there was no filming or pictures allowed of the game, but I was promised screen shots and footage which I can splice in later. I suppose that would make me a splicer, eh?
2K sanctioned off an entire separate team to work on BioShock 2's multiplayer, which was a relief for me to hear. I was worried from when I first heard about the inclusion of multiplayer, as I thought it might detract from the single player experience. With separate dev teams, it means each can spend all of its time making their part of the game as best they can.