Harry Potter defenders tend to talk about how imaginative the writing is, but from what little I've seen, this sounds like the conclusion of a TV generation. Rowlings may be a smart businesswoman, but she is no writer.
And whoever made the movies...good grief. I rented two of the things and lasted 20 minutes before sawing logs.
My teenage son is an avid reader. He devours books. Reads lots of fiction, classic and modern. Some of his favorites are Hemingway, Dickens, Twain, Rawlings, Cussler, etc. (Old Man and the Sea one of his favorites...must be a guy thing, LOL, I thought it was depressing.)
He's not really into fantasy/fiction, but did enjoy the Hobbit and Tolkein's Ring trilogy.
That being said, he loves Harry Potter books because he says they're fun. I don't think "great writing" is what makes these books appealing, I think it's more the fantasy element.