Harry Potter meets Jonathan Strange and Pullman's Lyra in Jonathan Stroud's Bartimaeus Trilogy, the first volume of which is The Amulet of Samarkand. While I don't know where the series is going yet, I'm really looking forward to the trip. With this book, Stroud manages to carve out a niche in the ever-more-crowded "wizard fiction" genre by offering up some fresh perspective and some unforgettable characters.
Young Nathaniel (or, to use his official wizard name, John Mandrake), an apprentice wizard, finds himself caught up in matters somewhat over his head when he (accidentally) stumbles across a plot to overthrow the government. Thankfully he's got a cantankerous and not-entirely-unwilling djinn of great age - that would be Bartimaeus - at his beck and call. Together the unlikely duo must infiltrate the plot, reap vengeance for an untimely death or two, and manage to get out alive.
I found Stroud's take on the parallel wizarding universe well conceived and well written, and the style of narration (alternating between Nathaniel and Bartimaeus) worked nicely. I really enjoyed the djinn's sarcastic and witty footnoted asides, but then I have a great affinity for such things. Dark, original, and engrossing throughout. Good stuff.