This is the 8th book in the Pendragon series, which I bet most of you haven't read. Bascially it's about a boy who discovers he can travel between worlds (called Territories) and it's up to him to save each of those worlds before Saint Dane (the bad guy, not a dog) turns them towards destruction.
The Pendragon series is an enigma. If I haven't read one for a while I have no desire to pick one up, at all. But once I'm reading one I'm completely hooked. I grew up with this series, literally. I read the first book and have bought each book right as it came out.
Give 'em a try. They're not half bad. Or a fourth bad.