SMG but so close between it and MK Wii.

Super Smash Bros. Brawl.

However, honorable mention goes to Resident Evil 4: Wii Edition, Super Mario Galaxy, Metroid Prime 3: Corruption and The Legend of Zelda: Twilight Princess.

Super Smash Bros Brawl, Super Mario Galaxy, Legend of Zelda Twilight Princess, and Zack & Wiki Quest for Babaros' Treasure

Brawl, I have it in my profile...

The Legend of Zelda: Twilight Princess hands down

Super Mario Galaxy is a fantastic experience that no one should miss, no two ways around it.

Honorable mentions go to Super Smash Bros. Brawl, Metroid Prime 3: Corruption, Fire Emblem: Radiant Dawn, The Legend of Zelda: Twilight Princess, and Resident Evil 4: Wii Edition.

I haven't purchased MKWii yet, I decided to buy Boom Blox instead (It's really fun ). I'm also planning on purchasing No More Heroes and Okami. I've only heard great things about these titles as well.

Super smash bros. brawl!!!!!

i would say SMG but its only because SSBB isnt out here yet :S

Wii Sports.

Quite simply, there is no experience better than getting drunk and playing it with your mates.

I haven't been able to get too into Brawl since my roommates at college didn't play it after the first week and it didn't work at all online for me. I loved the little I did play.