i dont think Wii has peaked just yet.
if we don't include the big end of year numbers;
- weekly sales 2007 averages somewhere between 200-250k
- weekly sales 2008 averages somewhere between 350-400k
the Wii has had a big holiday period this year and it's popularity is only going to increase because of it. people should not be surprised if next year the Wii sells 450-500k per week.
now i believe that will be the high point until Nintendo bring down the price and introduce new colors.