I cannot possibly recommend WW-Z enough. It's an extremely thoughtful book that is at once zombie horror, adventure, thoughtful political commentary, an exploration of human reaction to tragedy, and some viciously funny biting satire. I would also very very highly recommend the audiobook version which is fully casted with some people you might be expecting like Alan Alda and Rob Reiner.
I didn't really care for the Monster Island series. It was a bit on the military adventure side for my taste, at least the portion I read. Easy to check out as it's still on the web as a blog.
For small publisher/semi-pro stuf, I enjoyed As the World Dies by Rhiannon Frater or at least the first novel in the series--I need to pick up the next two. I thought it brought a more human and women's angle to it. I also enjoyed the two Dying to Live books by Kim Paffenroth. There were some parts that were a little clunky, but he's got a very good spiritual take on the whole thing and some odd twists to the usual zombie narrative.