I'll admit it. I chuckled slightly at the trailer. Not enough to want to go see the movie, but enough to make me shake my head and wonder at Bill O'Riley.
As for parody movies, I think you hit it on the head Roxie. Looking back at 'great' parody movies (Spaceballs, Men In Tights, etc) and more contemporary movies (Dodgeball, Scary Movie 1, etc), the one thread they all have in common is that they assumed you were savvy enough/smart enough/aware enough to get at least the majority of jokes, and didn't make the small ones that needed to be explained a major part of the movie (For example, the Dues Ex Machinima on the winnings at the end of Dodgeball.) However, these 'bad' parodies (The recent Scary Movies, Meet the Spartans, etc) is that they bludgeon you to death with the comedy. They assume you'll never get anything deeper than a Brit or Sanjaya joke, and the one or two deep jokes they put in the movies they over explain to the point that it's not funny. They're not subtle at all.