BioShock Infinite's marketing has been interesting. It's not that it's being dumbed down necessarily, more like it's being stripped back, right to the core of what the game is. This sort of thing frustrates certain people, but agree wholeheartedly with the decision. The above trailer is a good example of that direction. It's action packed, alludes nicely to the game's themes but never risks alienating the folks who know absolutely nothing about BioShock or the work that Irrational Games typically does.
I like it a lot. Trailers aren't supposed to be burdened with exposition. They aren't supposed to swing around promises of thematic depth. BioShock Infinite is a period shooter set in a strange land and this trailer gets that across expertly.
I managed to play roughly four hours of BioShock late last week. You can check out my early thoughts on the game here.