Sure, PS2 will remain the highest selling console, if you don't count the DS as a console :P
Anyway, I never expected Wii to pull off PS2 like numbers. Hell I was pleasantly surprised when it even passed NES's numbers. What I didn't expect however was for its sales to drop off so quickly and drastically. Though I guess with virtually no real third party support it does make sense in retrospect. Oh well, it'll still crack that illusive 100 million mark at least, and most likely pass the Playstation 1, which is quite an accomplishment in itself.