Following a familiar pattern in epic fantasy, this book (the first in a trilogy) introduces us to the main character, Azoth, who starts the book as a young street rat with nothing but his wits, and ends it as one of the deadliest warriors in the kingdom, with super-ninja powers, a magical talent, and possibly immortality. Along the way, he acquires a Wise Old Master, assembles a varied collection of allies, faces down old enemies, uncovers secrets, and gets the girl. So, it's pretty much a standard heroic fantasy, except the "hero" is an assassin who's done a lot of bad things to atone for. And right on schedule, the real adversary appears at the very end of the book, setting us up for the sequel.
This was a great story -- fast-paced, well-plotted, full of twists and turns and an interesting cast, and lots of action. The writing was a cut above average, but only a cut. Also, it was like a lot of Hollywood blockbusters -- a fun thrill ride while it lasts, but there's nothing deep or novel in it. Brent Weeks isn't carving out his own niche in the genre, he's just settling comfortably into the space occupied by others. Will I read the rest of the trilogy? Sure, I'd like to see what happens next. But this is still, ultimately, standard-issue dark fantasy; you'll enjoy it if this is your thing, but I can't see putting it on any "Best Fantasy Series Ever" list yet, though maybe the next two books will up the ante enough to impress me more.