Hm, it remains to be seen if WFP will ever be able to beat the original WiiFit's sales... I think it just might, provided Nintendo don't bring out another sequel too soon. It's cheap, so a lot of people who own the original will be upgrading, and I also think there will be quite a lot of people who will buy WFP w/ Balance Board, so that would boost its sales even more. The original has practically stopped selling now, so... it'll be interesting to watch.
Resort doesn't have a chance in hell to outsell Wii Sports, but that's mainly because of the bundles. Still, the game'll see incredible sales. 20m+ easily, imo. Same goes for WFP.
Oh, and congrats on your first thread! 
Quite a well-thought-out one, too!
Nintendo Network ID: Cheebee 3DS Code: 2320 - 6113 - 9046
