Better be the iTaco, and it should make tacos... cause I want a friggen taco right now.
Anyway, I am curious. First thing that comes to mind is that it is the iPhone 5... BUT I think it would be super hard for Apple, AT&T, Verizon, and all of the other iPhone carries to keep that a secret, so must be something different. Can't be a new Macbook, iMac, or Mac Pro since they refreshed all of those product lines recently. Can't be an iPad 3... cause... well thats just stupid to release a new iPad so close to the release of the current model.
So my bet is on a new iPod line revamp, or a new product entirely.