I doubt Nintendo knows their business that well. The gamecube was a piece of crap compared to the rest, and im sure even nintendo is surprised at how well the wii is doing. I'm continually amazed at the people I hear buy a wii. Considering the people who I hear buy it, I have to wonder if it's a fad. The wii seems like the new tickle me elmo. I'm really interested at seeing the results of the next wave of consoles. I personally don't think nintendo will do nearly as well (not that they'll do poorly) as they did this generation. But, maybe i'm completely wrong. Who knows.
The main reason I wonder if it's a fad, is that a lot of people are really disappointed in the wii. They pull it out at a party every once in a while, and shortly after they buy it it no longer gets any use. They think they're going to get a much cooler piece of machinery than they get. As soon as the initial wow factor wears off they fall back into their normal, nongamer, lifestyle. It's these kinds of people that caused the wii sales to skyrocket like they did. Nintendo pulled the nongamer into gaming for a little while. I just personally don't see them keeping most of these people there. But, like I said, who knows. We'll have to wait and see.
And yes, sony fanboys are having a hard time accepting that they lost this generation. Go visit blu-ray.com. It's almost funny how fanatical they are there.