I saw it, I enjoyed it, but... I wasn't "impressed" either.
It's not Tim Burton at his best, he hasn't been at his best for a while, and he just didn't do "enough" with it.
Then there's the fact that I've played American McGee's Alice and the plot has similar strokes to it, however, the one in Tim Burton's Alice seems... "thinner".
It was my first 3D movie, and you know, I'm beginning to think that people rely on the 3D to impress people too much.