Better than [book: Perdido Street Station]. I've read comments that the characters are less sympathetic, but I didn't find that to be so. Well, some of them, but they more than make up for it by being mysterious. Even though there's more profanity than I tend to enjoy, [author:China Miéville]'s writing is definitely high quality and well worth it.
As in Perdido, a very ambitious plot, but the setting is far and away more interesting.