Heavy Rain Is A System-Seller According To David Cage.

Aptly, that term is "system seller", and Quantic Dream's David Cage thinks Heavy Rain is just that.
[quote]
“This experience should be available exclusively on PlayStation 3, and we want people to buy a PlayStation 3 because of Heavy Rain. We’re really happy at the moment – and I hope it’s going to last – that when we go onto forums we find people watching the trailers and stuff and saying ‘this is the game that’s going to make me buy a PlayStation 3?,” said the Quantic Dream boss.</blockquote>

With Heavy Rain being such a unique experience, we wouldn't put it past people picking up a Playstation 3 to try the game. Either that or they'll just proclaim, "Do not want QTE only game," on GameTrailers' forums.