Sells more software on 360, moves more ps3 hardware.

Overall, I think sales will be 1.2-1.5 to 1 in favor of the 360, but as time goes by and the ps3 comes ever closer to the 360's install base, sales of GTAIV will even out. Once the game goes greatest hits, sales will probably be even between the two platforms, with a slight edge for the 360.

360 is going to beat PS3 on sales in this game, bigger user base for the 360.

I think they will both sell EXACTLY THE SAME AMOUNT.

The number is 999,999 per system.

First week = 360
End of Year = 360
Lifetime = Wii - with Wii zapper for shooting, Wii wheel for driving and balance board for walking, we can all dream, its a pity the Wii wasn't a bit more powerful, oh well there next console will make up for it

It's okay kermdfrag, Manhunt 2's more fun than stupid crummy old GTA4 anyway.

That is the dumbest thing I have read in freakin' days man.

Can we nominate this guy in the "Can you be banned for being too dumb" debate?

And in the end, I think that the PS3 version will sell more, although the 360 version should sell more at first. It's a game that harrows to the PS brand. The fans will come, slowly, and both versions should sell for years, although the PS3 version will likely end up having better legs. 

xbox 360 should sell more as it has 6+m more units sold ww. but it wouldnt be a stretch if ps3 version sells at par or more (dmc4 for example...)

I will say 360 without a doubt first week. Down the line, I still think the 360 version will win out, but it will be close.

Here's my rationale. The 360 is essentially tied with PS3 in Europe (even though it is still ahead by a large margin, we can pretty much tell which way the wind is blowing). I anticipate a higher level of sales of the game on the PS3 there. However, I don't think the ratio will be higher than 1.5:1. The 360 owners aren't simply gonna ditch their system. They own it, so they might as well buy the biggest game coming out for it. It's not economically practical to switch systems, although multiplat owners I think will opt more toward the PS3. Obviously in Europe, there will be a bigger uptick in PS3 sales seeing as there are a number of regions where the 360 is simply not that viable anymore (the Japan syndrome).

However, NA will be an entirely different story. With about 11.5 million 360's to 4.5 million PS3's, as well as the 360 occupying a more dominant position among gamers here, sales will skew toward the 360, both for new purchasers and multiplat owners. Add to that the fact that the 360 overwhelms the PS3 in total install base, there is no way it can make up the difference. Considering the similarity in userbase (shooter-heavy action fans dominate on both systems), I think it's fair to say both will have similar attach rates. Assuming 1/4 owners get the game, that's a ratio of almost 2.5 to 1.

Japan will be non-issue. GTA games have put up respectable numbers there in the past, but that was on a dominant and established PS2 platform. PS3 has barely sold 2 million in Japan, and is putting up absolute ass numbers right now. It won't make a difference, this is simply not a game that will surge the system there.

While Europe will see higher sales on the PS3, the difference won't be that big. America has a far larger audience of 360 owners with a proven consumer whore mentality, and that will be the deciding factor. I think even in the long term, it will be hard for the PS3 version to overcome the deficit. And there is the possibility that the release of the DLC (especially if timed with a price drop), if it's really all that and advertised, could boost GTA4 even further later into its life.

 I think it should be pointed out that with a game like DMC4, Japan becomes the swing vote. I don't think that'll be the case here since GTA is WAY bigger than DMC and is western-centric.

I'd go with 360.