I have a friend who wrote a bestselling novel and was later accused by a woman of plagiarizing her work. Fortunately it never made it to a lawsuit -- when confronted by the evidence disproving her claim, she backed down. (As it turns out, their ideas weren't even remotely similar.) So this kind of thing happens all the time. It's tempting to say that the plaintiffs are just looking for money, but I think a lot of times they honestly believe they've been aggrieved.

The authors of Holy Blood, Holy Grail had spent the last thirty years insisting that their book was non-fiction, which means Brown is free to take "facts" from it, the same as if he wrote a Western and used a biography of Jesse James as a source.

Unfortunatly, you focused on the wrong word. The important one as it relates to this discussion is: derivative.

Exactly, the word "derivative" is relevant to the discussion while the word "garbage" was flamebait. He was just trying to head off a side argument over the actual quality of Rowling's work, which has nothing to do with the topic at hand.

The visuals in the movies are not the books

Someone mentioned the quiddich games, but book quiddich is about characters and whats going on in the stands and in Harry's head