I'm thinking Japan. Americans are too manly to play with dolls.

The game will not sell in Japan since it's definitely not a game made for the Japanese market. I think it will sell a bit more in the US than in Europe, because overhyped games tend to flop harder in Europe than in US. Overall I'd say lifetime sales will be about 100k in Japan, 700k in US and 400k in Europe.

It'll sell better in Others, most of the people I know who have a PS3 don't have much of a reaction when I ask them about it.

I think Europe will be easily in terms of units LTD: I won't speculate and do not particularly care about attach rate in this case.

I'd say
700K in others, giving it around a 9% attach rate.
Maybe 400K in America, with a 6% attach rate. Really, this number is pretty swingy. Depending on how they advertise it it could go up or down 200K
100K in japan, for a 4% attach rate, but there's a nontrivial chance that it becomes big in japan. Japanese culture has a lot of fads, and if this hits just right I could see it selling 400K+.

Europe

I think Europe.

I feel European's are more open to quirky ideas. Maybe because there are so many different countries and cultures in one continent.

@OP: I'm inclined to agree with you on all points except one.  I think it will sell very well in NA, though the attach rate won't be as high as the other regions.

It depends on a lot on marketing, in addition to word of mouth. In Japan, they're already heavily pushing LBP. :D

Europe...

America like most....