Let's get some numbers in this thread so it's not just an opinion-fest:
Smash Brothers: 5.36m
Mario Kart: 4.31m
Wii Fit: 2.55m
Smash Brothers has the highest sales, and has not been released in Europe as yet. (Wii Fit also has not been released in America.) Since Brawl has the highest numbers, and will assuredly pick up another 2m sales in Europe, I'd have to say it's the winner for 2008. I actually think both games have a good chance to outsell it lifetime, but Smash Brothers is a much more front-loaded game. That will help it in this calendar year.
End of 2008 totals: Wii 42m, 360 24m, PS3 18.5m (made Jan. 4, 2008)







