It's easy to look at a list and say "this is going to be hard to do". But consider the massive install base for Wii which should be at least 60 million by the end of the year.
I think it's really going to come down to legs with this game. If it has the legs of Mario Kart Wii, 11 million will be no problem (it will probably be more). However if sales taper off it will probably sell more along the lines of Super Smash Bros Brawl or Super Mario Galaxy.
Having long legs will depend on if this game can hit the mainstream/non-gamer ends of the market. My gut tells me it will, but I sort of shudder when I hear about the game being "harder than contra". It's good for core gamers, but I wonder how the mainstream audience will react to it.
Another very important factor is Japan. This was a huge factor in the success of NSMB DS. It sold 6 million over there. If they do the same with the Wii version, consider 11 million reached.
