I have it for the x360 and think its alot of fun. I too like COD4.. i really enjoy the multiplayer portion of waw.. i do like cod4 but i've been having more fun playing the team deathmatch on waw. Also, they have a zombie mode which is great fun when you have a bunch of friends playing.
not to mention, co-op on most of the single player campaign, including competitive mode..
yes, its more of the same with cod4.. with a ww2 skin as people have mentioned, but if you like cod4, then you will like this game..