Looks like Dan Houser has indirectly spoken out on the PS3 in this article (View this scan, top right of the text area
Speaking for myself, because of the games out there at the moment, I wouldn't go and spend six hundred bucks [$999AUD] on one of those machines yet. There's not enough interesting software, unless you happen to really like having an expenisve box that shows off graphics on some really uninspiring games, that's your business.
Obviously referring to the PS3 there. Some of you may read just that and think "Ha! Even Dan Houser hates the PS3! Sony must really
suck!" well sorry to burst your bubble, you're wrong:
We are trying to make things that will make a large number of people go out and buy the machines. We have to do that by showing stuff early because it's a big purchase for people.
Now if you took the time to read that quote too, you can more clearly understand what Dan is saying here. In the first quote he is speaking from any person's point of view, those who want to make sure every cent of that $600.00 is well worth it. In the second quote (the following paragraph to the first), he basically states that Rockstar is trying to give the people a reason to go spend their money on these consoles, by creating a truly amazing gaming experience that should not be missed, of course this experience is GTA IV.
No doubt in my mind they would've done that anyway, even if they didn't intend to.