As I already mentioned: If the movie is good and I like it, I will watch it in cinema of course. Another criteria would be sound effects that you cannot have at home in a ripped version.
Of course this is very dangerous: if the movie is crap I would never go and watch the film in the movies.

If there are trailers on P2P networks first there is a good chance that people like it and it a kind of completes your advertising strategy, so ppl will go to the movies.

Another thought on downloading the riped movie: I think not all of the ppl who download the movie do that because they don't wanna spend 5$ for the movie in cinema. I think many of them download the movie if they liked it to watch it again. I mean a DVD isn't cheap as well and if you are cineastic but not much money available this is a good possibility to build up your home movie collection (for free). Like ppl did with VHS video cassettes in the 90s (or is VHS only a European format? I hope the point came accross).