I went to the theathre with pretty high expectations and left having my expectations actually surpassed. (It might even be better than Batman Begins!) Christian Bale was amazing, as always, and Maggie Gyllenhaal did a great job playing Rachel Dawes. But I was most impressed by Heath Ledger's Joker. I'd read that his portrayal of the Joker was what the character's creators had always envisioned him to be - he's both funny and demented. I suggest, reading "The Killing Joke" comic book (esp. for those not familiar with Batman history) before watching the movie; it really sheds light on the Joker's persona. I'd be surprised if Ledger doesn't win some sort of awards for his performance. Also, go see the movie more than once - you'll see things you miss the first time.
Thoroughly enjoyed the movie! I love that they brought Marion Ravenwood back, and referenced Henry Jones Sr. and Marcus Brody. Shia LaBeouf did an incredible job, his and Harrison Ford's characters interacted very well. The movie was fun, well filmed, good character development, and interesting story line. This is a must see for any Indy Jones fan!