Very good movie. It is exactly what you'd expect it to be, with the "zombie" part really just being a slight twist on any other sort of terminal condition, except of course you can't just let nature take its course with zombies. So there isn't really any sort of surprise or anything, you pretty much know where the movie is headed from the first few minutes (or the trailer). Still, it is a pretty powerful movie even with being predictable. Granted, I don't watch a ton of this type of movie, so maybe I'm just viewing it through a different prism, but I liked it a lot. If you are looking for this kind of movie, and are aware that it isn't trying to be anything else, I think you'll like it too.
I know Arnold isn't really known for his acting chops, but I was incredibly impressed with his performance in this movie. He needs to do more like this, because he can do a lot more than blow shit up if this is any indication.
Two thumbs high, with the caveat that you know what to expect and don't judge it against false expectations.