What's this then about a new Rock Band game?
The reference comes from, of all places, Vic Mignogna, best known as the voice of Edward Elric in Fullmetal Alchemist and his work in quite a few Dragon Ball Z games.
About 6 minutes into part five of a six part recording taken from the Winter SAC-Anime convention Mignogna falls face first into what appears to be NDA-breaking material.
"I did this, it's like this Rock Band video game that's coming out... Oh, I don't think I should have said that," gets out before stopping.
At which point another panelist, Laura Bailey, pulls him aside and whispers things in his ear and they change the subject.
Brief, innocuous, possibly apocryphal, but still tantalizing.
If it is indeed a Rock Band, Rock Band game, my money is still on it being the Beatles title Harmonix is working on, seeing as they've said that that game is taking up all of their time right now.
Of course it could be Dragon-Ball Z's Marching Musical Mayhem or any number of rhythm game knock-offs.