The Promise of Pokemon is what sold me a DS. I never cared about any other exclusives, but I enjoy Fable a lot.
A 3D Pokemans that wasn't Colosseum but a legit Pokemans game is the tipping point for me to get a 3DS.
Microsoft needs a new IP to draw people in, I am one of the biggest fans of Halo and Gears out there, but both series have declined this gen and don't have the luster they once had. Maybe Black Tusk's new IP turns out to be as big as they hope? Or maybe one of their other studios they've opened releases the next big hit. I don't really know exactly where it is going to come from, but they do need something big if the next Xbox is going to attract the core market that will be ready day one.
I agree. Halo and Gears can still bring in some numbers, but Microsoft really has to know by now that they're going to need something else to draw new people in again. I think that's going to be a game by either Black Tusk or Rare.