I'm quite taken by Kathy Paur's summary of the liberal values of the Harry Potter book series, which she presents together with some other takes on childrens' literature over at BOPnews:
"Harry Potter is ostensibly a self-reliant individual taking on the worst evil-doer of all – but the Potter subplots hold significant populist lessons: Pure-blood elitists are mean people you wouldn’t want to befriend. Discrimination against lower socioeconomic classes (chiefly house-elves, goblins, centaurs, and were-wolves) is not only immoral but may have disastrous consequences (the Order of the Pheonix worries that the goblins will support Voldemort if he promises not to treat them like second-class citizens). The media (The Daily Prophet) can be bought by those in power and used to mislead and endanger the citizenry. An ineffective government (the Ministry of Magic) which isn’t committed to the well-being of the people is more than capable of ignoring real threats and punishing whistle-blowers. And free, high-quality education is wonderful fun."
There is an interesting discussion developing in the comments too. On the other side, it seems that there are people on the right willing to run with all sorts of inflated or satirical claims about the books promoting the spread of the dark arts.