He read the first book in one 24-hour period. He seems to enjoy them so far, having started the second one right after he finished the first.
I have moderately enjoyed the books, though they haven't been a complete surprise to me because I have seen snippets of the first three movies.
If I had one criticism it would center on the lack of character development of Harry Potter. I feel as if Hermione, Ron, and even Draco are more rounded out than Harry. He seems to always be reacting to things and he doesn't seem to possess much of an inner life outside of the context of his parent's death and Voldemort.
For a character who is supposed to be "the hero", he seems to lack substance.