I agree with the other guys that Rayman and Monkeyball NEED to be played with other people to really enjoy them. In fact I won't play Rayman without at least one more person. If you are planning on getting Warioware I would add that to the list of multiplayer required for enjoyment.
These are the games that I am most looking foward to in the upcoming months.
Warioware Smooth Moves - After this I should have enough party games to satisfy my friends and I for the rest of the year.
The Godfather: Blackhand Edition - the videos look REALLY fun
Sonic and the Secret Rings - Sites have me hyped up for this one, hopefully it wont disapoint. It looks somewhat promising though.
Tiger Woods 07 - I hate Wii sports golf, so this is a no brainer for me. Barring awful reviews this is one I will pick up the week it comes out.
No More Heroes - Suda 51's next Nintendo project looks to retain the art style of Killer 7 while adding some much needed boosts in gameplay. Niiiice.
Super Smash Bros Brawl - My biggest beef with SSBM was the lack of people who wanted to play the game with me. Online play should fix that, plus I've always wanted to maim Pickachu with Solid Snake.
Mario Strikers Charged - I missed out on the gamecube version of this title, so if this gets solid reviews I will make sure to pick it up.
Battalion Wars 2 - I really loved the first Battalion Wars. It was a fun, but flawed experience. Hopefully Kuju Entertainment can fix the problems of the first game and make this a Wii owners dream come true.
Mortal Kombat Armageddon - Again I missed this game for the current gen, but if this version gets good reviews I will be getting it. I just watched a video on gamespot in which series creater Ed Boon showcased the Wii controls. It looks like it might turn out pretty decent.
Super Mario Galaxy - I haven't loved a Mario game since Super Mario World, so I am expecting big things out of this title. Lets hope it lives up to the enormous amount of hype surrounding it.
Anyone who doesn't already own or hasn't already played The Legend of Zelda: A Link to the Past needs to download it from the VC. It was released yesterday and for $8 its an absolute steal. Go buy it now.