Phillip,
I am glad you see the main problem with the books being given to children without guidance. There is a concerted effort being made, not neccessarily by Rowling or even by Scholastic, to tie in the reality of witchcraft with the whole fad. Occult groups are gleeful at the amount of interest and publicity they are getting because of the books popularity.
I don't think taking your 17 year old daughter to the movie, or even letting her read the books is going to get her into the occult. But if these books are being given to kids of the age where they are specifically marketed (6-11 years), and they are shown through them that magic is neutral, and it can be used for good, and if you are special, than you don't have to obey the rules, and many other lessons that are contrary to God's word, than I think it can cause a problem. I have seen a very close association with SOME kids that attend our church between their fascination with Harry Potter and dabbling in occult practices. You would not believe some of the things a few of the bus kids have told us they believe or have seen practiced in their own homes. Harry Potter is not pure fantasy, it is based very closely on real occult witchcraft, something the Bible condemns clearly. I am glad you see some of the dangers in the series.
Steve,
I agree that it is not a sin to read about witchcraft, but I would question the necessity, especially among children. I am glad you would recommend reading them and discussing them with children, I am just not sure if that is really the best way to teach your kids about witchcraft. The books IMHO paint witchcraft in way too positive a light, in addition to being not pure fiction, but based on real occult magic. The witchcraft is only the beginning of the problems I have with the books, but it is enough for me. I am not even convinced they are even good literature, having read 2 out of the 4 books, and checking my Lit Crit notes a little. Being a NYT best seller is not my measurement of any author's work. I mean, Steven King sells a million books, and writes ****.