I enjoy reading Isaac Asimov's books, and I knew going into this movie that there wasn't going to be much taken from Asimov's "I, Robot" other than the title and his three laws of robotics. In fact, had it been up to me, I would have passed this movie up completely. (I'm not that big a fan of Will Smith.) However, my brother-in-law is in town with his wife this weekend, and they wanted to see it, so I went. I was very surprised, in a good way -- I gave the movie an 8. Sure, it's not an Asimov adaptation (the end credits read only "Suggested by Isaac Asimov's novels"), but they came up with an enjoyable storyline that was pretty true to Asimov's overall concepts. Since this is a spoiler-free thread, I won't get into any specific details.
I will mention one thing, though: the voice of the robot that got the most screen time was that of Alan Tudyk, the actor who played Wash on Firefly. Pretty cool.
Johnathan