I really liked this game. I think it's probably because it's just a never ending series of zombies that are coming after you. You even got some variety with the hockey mask guy. I don't like it how you have to reload your shotgun every time. Maybe I'm doing something wrong? I love games that give you a lot of mobility.
This might sound crazy, but sometimes getting yourself cornered is a good thing. It just comes off as more organized to me. There is of course the problem of jumping. You probably could have put some music in it. Still very nice.