I still see uneducated consumers (read: Casuals) buying the PS3 for it, simply because GTA is associated with PS2 but one should never underestimate marketing power, MS, Sony or Nintendo.

75% boost for about 3-4 weeks for 360, and a 50% boost for ps3 for about 3-4 weeks, with ps3 currently beating 360 worldwide, this will leave them drawing for a while. Then MGS4 will arrive and ps3 will comfortably retake the lead.

Focusing on consoles I expect to see PS3 get much larger boost due to the fact it has smaller install base and that given GTA genre its much more likely that many people who would want to play it on a 360 already have one.

360 should sell more units of SW than PS3 though, but as a console it will not benefit from a sales spike nearly so much IMHO - although the only comparable game right now is probably DMC4, which is latest version of a PS2 franchise that went cross-platform, which has sold effectively 50/50 between the two consoles, so who knows...

+ 30% boost for PS3 and 360 during 3-4 weeks

I can't believe we haven't seen more mainstream marketing on the part of the console makers trying to get the jump on sales. You know like a GTA commercial that says Jump in or has the PS3 logo at the end. Seems like there isn't a lot going on in that direction.

ps3 will win

I think it will move just more PS3's because people associate GTA with Playstation.

Right, I guess I was trying to list games that will come out only for one console during the months right around GTA IV which might factor into people's decisions to buy one console or the other.  Granted, UTIII is already available for PS3 and is now being added to the stable of 360 (fps) games.

Ps3 and 360's market share SHOULD increase with the Wii's decreasing.