As some others here have said, I also feel that Michael was robbed of his childhood, developed a mistrust of many adults, and wanted to relive his childhood in some way. And since he had plenty of money, he could do it in a very "big" way, with Neverland. He never, ever struck me as the predator type. As far as the sleepovers are concerned, I have the impression that he was just a bit naive about that, maybe not realizing how outsiders would view it, since he himself was so innocent. As someone else mentioned, I've always felt that he tended toward the asexual side...even his crotch-grabbing and other posturing on stage always seemed very non-sexual to me.
All that being said, I think he was a wonderful, talented performer.