The first Bioshock is a pretty unique experience (err, unless you played System Shock 2...), Bioshock 2 on the other hand is more of the same, with a great deal of new features. I think more of the same is what a lot of us wanted, I for one really like dropping back into the world of Rapture and picking up where I left off. It is very familiar, but yet there are plenty of surprises. Not been there done that familiar, but pleasant nostalgia familiar. There is plenty of new stuff in there, and an entirely new storyline. This is more of a fan adventure/mystery story than the dark dystopian novel like story of the original, but I think they did a really good job making it a fresh new tale from the world of Rapture, without making it feel like they it had to be tightly woven to or live up to the first games story (from what I have seen of it so far, anyway). Rapture in the first game was a huge place that felt like it had many tales to tell. BS2 definitely fits into this.

However, talks of turning it into a trilogy of games and even a film on some back burner some place makes me a little leery. They stand a good chance to really beat this poor franchise into the ground and severly cheapen it. I think a sequel was a great idea, but I don't think they should take it any further, at least not for many years down the road.