Also on the note of sequels, while the general trend on the Wii is that they ain't built for success, it certainly worked for Ubisoft with the Rayman Rabids game. one of the few exceptions to the rule sure, but they've got the foundations to build on.
My worry is that it's different markets. RRR is aimed at the younger audience, who most likely will want the sequel every year. Let's Dance I'm not sure is the right crowd who'll buy a sequel, I think it's possible though.