GTA IV is going to have a massive effect on the HD console war.
Will all the PS2 owners who have been holding back now buy a PS3 and keep their loyalty?
Or will they be tempted over to the 360 to get all that exclusive GTA IV extra content? And Halo 3. And Live.
Microsoft are going to spend many tens of millions on marketing their GTA IV exclusive content to try and ensure the second of these scenarios.