The hype is outrageous. I agree the publishing industry is too much about blockbusters. Harry Potter and the Death Hallows is the blockbuster of blockbusters. But when it comes to J.K. Rowling's novels, I say just read and enjoy. Just do not start one of the books when you have something due on deadline!
The Harry Potter books are fun to read. The characters are ones any teenager can identify with as can anyone who was once a teenager. They remind me of Robert Heinlein's teen novels. Heinlein, the great science fiction writer, wrote that those novels taught him his craft. He had to have a plot that would keep them reading. He needed to keep his vocabulary direct and straight forward. And in those days sex and violence were not available to make up for a lack of craft.
Some Christians shun Harry Potter books. I will not rework the arguments about whether these books are a threat. There are three excellent essays that do a better job than I would: (1) "An in-depth analysis of the literary use of magic in the works of J. K. Rowling, J. R. R. Tolkien, and C. S. Lewis" by Steven D. Greydanus. (He also reviews the films on his DecentFilms.com website; (2) "Harry Potter's Magic" by Alan Jacobs; and Charles Olson's posting, "If you thought I was anti-Harry Potter..." on Ignatius Insight Scoop.
In the Harry Potter books, the magic is a fiction. Like the devices of science fiction, the reader needs a "willing suspension of disbelief." That is not the same as believing in magic.
Rowling is very clever in the imaginative devices with which she fills her world. After decades of moral relativism and the denial of evil, it has been refreshing to have a wildly popular source of entertainment clearly describe Good and Evil at war with each other. Ditto for Star Wars.
Rowling is also an excellent craftswoman. That is not to claim she is T.S. Elliot or Fyodor M. Dostoevsky. The elite looks down its nose at her, but they look down their noses at J.R.R Tolkien and C.S. Lewis too. Rowling and I are fans of both! None of the major publishers would touch her first book. Ironically, they are now the hype masters for number seven!