According to GoNintendo.com:
Metroid mania is in full affect for alot of people. Although it took a while for Nintendo to step it up and deliver pursuasive advertising its really good for the game. I am not sure how much the game has already sold but I am convinced that its around 500,000 preorders. Thats pretty good! But not a good as Halo, but Halos like a cult. I hope it will be as good as Bioshock, and I also want really great story to wrap up the Metroid franchise. Judging by the videos like Aurora and PED suit there will be a good story, and did you know that everyone will talk.