"Pretentious" or not, isn't that what a game developer is supposed to do for his game/interactive art/inema/whateverthehellhecallsit?
I, personally, am extremely excited for Heavy Rain and hope it delivers on everything Quantic Dream is pushing for and more. The way I see it, Heavy Rain is a step towards making better stories and better interactivity within those stories, so much so that it could be a "gateway drug", so-to-speak, for future games that want to try and push storytelling and interactivity even further.
Could you label this game as a long quick time event? Sure, I guess, if you're "pretentious" enough. But I don't see any other damn game working so hard just to give the player actual choice instead of "Execute the hostages........OR DON'T!" or just trying to move away from the absolute shit stories that most games have nowadays (just watch some of this stuff. [http://www.escapistmagazine.com/videos/view/unskippable] Watching many of those has made me realize how absolutely generic most games can be).