I just finished reading Harry Potter #6 aloud to the boys, and since all 607 pages of text passed through my eyes, brain, and speech, I figured I should review it like everything else. Then I realized, who cares what I think? Let's ask the boys!
Apparently what stands out is the ending. Aidan didn't like that the locket was fake and not a real Horcrux (oops, spoilers! Oh, and Dumbledore ... um, never mind .. although it's been in a Simpsons episode for about 5 years now). Sam says it was not his favorite, but his favorite was The Goblet of Fire. The sad ending got to him too.
But I think they'll agree it's worth it when we read onto book 7, so much of book 6 is really a set-up for that. They'll find out once my voice has time to recover.