Yeah, there are a lot of great trailers over the last couple years. Brings back a lot of memories. :)
A few people on my forum who have beaten the game with via ways I don't approve of have said the campaign is between 16-20 hours. Obviously, that is an approximate and could be slightly different in the final game. Hope that answers your question. :)
This guy gives journalists a bad name. Fake name dropping? Not cool.