I think people need to know what genre Heavy Rain is before they say "There's no gameplay". Do games such as Myst lack game play because you can't fully control your character? Are RPGs lacking in gameplay because you have to stand in place? What about RPGs that don't even have combat?
A game doesn't necessarily need to be an action title. I'm looking at Heavy Rain, not as a fighting game, or a Splintercell/MGS4 esque game, but in fact, a game that has many gameplay elements, but without the technical gameplay mechanics.
For e.g. you have the stealth sequence we saw with the journalist girl. You don't have to be an expert at SC, nor precisely push the analogue stick so that you move fast by silently. Instead the stealth is based on common sense and logic, with you deciding if you're going to go for the garrage, or wait for the guy to move (and where to hide). The game also borrows from horror games (I never played RE but I'm assuming it also borrows some horror game elements).
I hope it'll be mostly dialogue based, and getting clues about the character. If the guy that works in the dump sounds suspicious, and you catch on it, you'll be making sure to not put yourself in a vulnerable position. You'll try to build trust with other people, etc.
Don't worry about the QTE, that's not going to be the main gameplay. The main gameplay is dialogue, and using common sense to assess situations.
