A few days ago, i started playing Fifa 08 on the Wii. Its a football (soccer) game and it was released some time ago.
But i noticed something. During january, football teams make transfers. Which means buying/selling players.
Fifa 08 was released before this date (by a few months) and they seem to have the latest squads already updated.
Example: Chelsea bought Anelka in Jan....Fifa 08 updated it automatically.
Example2: Spurs bought Hutton and Woodgate, again Fifa updates.
So there you have it, its not exactly 'downloadable' but the content is there, and it shows that Devlopers arent just leaving the wii to die, they are making the effort.
So behind the scenes, there is actual downloadable content, you just need to pay attention.