The multi player is surprisingly fun and this comes from someone who only plays COD4 and GRAW2 online. I have noticed that knifing people can be very similar to the chainsaw in GOW before they fixed it. It is not even close to where a 360 game should be relative to frame rate, smoothness and graphics but beings I am a fan of the genre I guess I am partial.
I would tell you to wait a few weeks and go to your nearest gamecrazy or gamespot and pick it up used.... or rent it. Either way you will have some fun