If it moves 1m units, it will have done quite well. That's asking for nearly a 1:6 attach rate (about a 1:7 rate by the time it releases), which for a game like Bayonetta, would be highly unusual.
Personally, I'm not counting on this one staying a Wii U exclusive. If it tanks, they'll want to recoup losses by selling it on other platforms sooner than later. As for expecting this game to sell any significant number of consoles... I for one, have no intention of buying a Wii U for Bayonetta, and I don't think I'm a part of some small minority of Bayonetta buyers/players who won't buy another console just for the sequel. It just isn't a hardware seller.
But more importantly, we don't even know how good the game will be.







