I own RE4 on Wii and it is a really good game from the first 5 seconds of gameplay I cannot get past. The game looks and controls great, I just have not been able to get into any RE game, I will probably just unload it.
No More Heroes - I love this game personally. I really enjoy the gameplay and style of the game and so far I am enjoying myself immensely. I can see myself replaying it just to hack guys up for 30 minutes.
Mario Kart - Great online game, and I enjoy the Grand Prix play. Hey, it's Mario Kart, what is there to say?
Guitar Hero 3 - Good game but I have not picked it up much. Just is more of a party game and is best with other people.
Metroid Prime 3 - I just bought this, but I havn't played it yet, I am psyched.
Madworld - Bought it last Thursday and sold it on Ebay. I would rent before buying this. The style is awesome, the gameplay is good, the story is surprisingly engaging. There is a lot of violence, but that didn't really bother me (See NMH above), I can't quite put my finger on it, but something about it didn't settle well with me. It is fun though.