Since when does Twilight
count as urban fantasy? That takes place mostly in extremely rural Washington.
My personal favourite in the genre, though I haven't read a lot of it, is probably Neverwhere
by Neil Gaiman. I don't think I've ever read a book that takes advantage of its urban setting quite so much as that one. Though Mark Millar's The Good Fairies of New York
, which I recently read for the first time, does come close. However, I didn't find the plot as engaging as Gaiman's work.