A somewhat popular blogger holds no brief for Pottermania, but his commenters are more diverse:
Curmudgeon! If I had young kids, I’d rather they were reading Harry Potter than wasting away in World of Warcraft, collecting enchanted unicorn testicles for Kaaleth the Bold of Shrivenshire. J.K. Rowling may have singlehandedly forestalled the end of literacy by a generation – and the books aren’t half bad to boot.
I’m just glad they’re reading something, though I did find a Left Behind paperback in my kids’ pile at the library and deftly flung it aside. Not all series books are good.