It's not difficult to find all sorts of stuff written on how the experience of going to the movies has changed over the years. Much of this is attributable to the rise of the home theater and the rise of the big cineplex.
Almost all of the commentary on this points to the general increase in plain old rudeness among theater-goers. Talking, chatting on cell phones and behaving overall as if they are in their own living room rather than a movie theater.
All of these are valid complaints but they leave off one very important reason that attending movies these days just isn't all that fun: the demise of the sense communal experience. The inverse of people making too much noise during the movie is that people sit on their hands during a movie- especially a big, fun summer film.
I attended "Pirates of the Carribbean: Dead Man's Chest" this weekend and was really surprised at how quiet the audience was for an opening weekend. Sure, not everything worked but there remained enough funny/ exciting stuff that should have provoked some sort of reaction out of the audience. Instead: nothing. Crickets.
I can put up with cell phones, crying babies and people talking. But the only reason I still go to the movie theater is to experience a movie with a crowd. If the crowd might as well not be there then I don't see what the point is...