One of the perks of being unemployed is you get a chance to catch up on a lot of reading and movie watching. I finally saw The Illusionist today, and just to get this out of the way, I don't know why people think you can't like both this movie and The Prestige. I've seen them both, and the storylines are pretty different. My recommendation - watch them both.
What did I like about the movie? Besides the twist in the tale, I thought the characters played not just their parts well, they played well with each other, making the engrossing script that much more absorbing. Ed Norton is one of my favorite actors, so having him play the protagonist might have biased me a bit. As I was watching the movie, I realized that this is one of those perfect date movies - it's not too gory, there is a definite element of suspense and a love story that tugs on the heart strings - all the things girls are suckers for :)