First, Petrucha seriously ROCKS. He prose is always facile and engaging-- he's probably the kind of writer you could entrust with the most random of assignments and he would produce something brilliant. ("Write about a boy who.... lives with a retired super hero... in Bermuda... and gets involved with... a dolphin and.... the mafia! Go!")I did NOT see the ending of this coming.
The second big strength is BOOK DESIGN. At 427 pages, this could be daunting, but it wasn't. The cover by Greg Stadnyk is awesome-- I want to do an entire post on his covers because he really GETS it. The pages have plenty of white space, the text is not tiny, and there are 85 chapters, but they are all short.