But I think I missed the point. The reviewer said "Harry Potter grows up." Or in this case, Quentin, from The Magicians by Lev Grossman, goes from being a genius high school senior in Brooklyn to being a first year student at Brakebills, a five year magician's college in upstate New York. Sign me up!

J. K. Rowling understands that, and Lev Grossman gets it too. His older students may transform themselves into geese and fly to Antarctica (shades of The Once and Future King!), but they also sometimes drink too much and sleep with the wrong people. If you ever wondered what a Hogwarts grad might do for a living if they didn't become an Auror, or play professional Quidditch, The Magicians suggests some possibilities.
Maybe it's the juxtaposition of mundane and magical that we like so much. Harry Dresden still has to get around Chicago in a cranky Volkswagen Beetle despite the presence of demons and pixies in his everyday life. Magic doesn't solve everything, and in fact, often makes life harder. In The Magicians, Quentin discovers that having magical powers is no more a guarantee of success than a degree from Harvard or Yale. As a reader, I guess I just like magic for its own sake, because it makes "real" life a little bigger, a little different, and a lot more interesting.
I'll leave you with one more nugget for thought: are there any Jewish kids at Hogwarts?