Hidden away on the PS3 release of Bioshock is a trailer for the sequel. The new game will be called Bioshock 2: Sea of Dreams.
Unfortunately, the only recording of the trailer on the Internet at the moment is somebody recording the trailer, off of a television screen.
But, here it is.
It looks like Bioshock 2 might be all about the Big Daddies rising to the surface, and messing with us land-folk.