Note: I've linked to Apple's trailers, the links are likely to become invalid over time. Just google the movie names and you'll find the official sites.
* Wanted This one was completely unknown to me until this morning. Angelina Jolie & Morgan Freeman in an awesome Mr. & Mrs. Smith meets Transporter kinda flic.
* Mongol. The Genghis Khan story.
* Indiana Jones - Kingdom of the Crystal Skull.
* Hellboy 2 - The Golden Army.
* IronMan. Starts tonight (2 May 2008).
* Bangkok Dangerous. Nicholas Cage plays an assassin in Thailand.
* Get Smart. Action comedy remake of the classic series with Maxwell Smart and Agent 99.
* WALL*E. Pixar's next, about a little lonely robot.
* The Spiderwick Chronicles. I just found this on Apple's site, however it says Feb 2008 and I don't recall seeing it in previews or commercials. The official site says DVD June 24.
* Batman - The Dark Knight.