I recently saw it. Spoilers will probably follow. For the most part, I loved it. I had some doubts that a single actor could carry an entire movie. Will Smith did an awesome job and I walked out of the theater pretty much wowed. I loved the scenes of post-apocalyptic New York.
I would have liked a little more background about Robert Neville and more backstory. I also thought that they made the infected humans were a bit too obviously cg and were a little unbelievable–strength, speed.
But none of these things detract from the fact that I was pretty much glued to my seat during the movie. Imo, a great movie and well worth the price of admission.