Glancing through the now quite long Harry Potter thread at a Yglesias's place I'm rather amused. Or bemused. Or something.
I always find it quite fascinating when people seem to get angry because you don't like stuff they like or like stuff that they don't like. It's one thing if someone's making a definitive claim such as "Harry Potter and the Chamber of Secrets is the greatest novel in the English language since Middlemarch," or similar. Such statements can inspire genuine discussion and/or argument. But that's something different than "I like Harry Potter" being responded to with "You're an idiot for liking Harry Potter."
Most of us like and enjoy a full range of stuff from low brow to high brow and everything in between. High culture, pop culture, trash culture are all part of the mix. I'm sure there are a few of those rarified individuals who are never sullied by anything that the rest of us mere mortals enjoy, but who the hell wants to talk to them.