There is NO freakin way after the first part of the "series" that it is even feasible to proctor a guess as to what the 2nd installment is going to be about. Mark my words though, come the end of the year I believe all speculations as what to expect will all be wrong, and look for the next one to be even better. I mean think about it. If you can create something like Bioshock, you cant out do yourself. You can only add to it, and twist the story along. Either backward or forward. It took some seriously creative minds to forge Bioshock 1, so you know they have some wild, crazy shit cooked up for part two.