GTA3 was the 800 pound gorilla in 2001. It was the big Game of the Year, and being exclusive to Sony, pretty much pissed on the parades of the GCN and XBox launches. It didn't hurt that it was further boosted by MGS2, Devil May Cry, Grand Tourismo 3 and Final Fantasy X, but by and large the buzz was all GT3.
In a few months, GTA4 is coming out. I know some PS3 boosters are expecting this, in concert with other exclusive titles, to save the PS3. Of course, this time it's not exclusive, and 360 fans are fully expecting its release (along with their own exclusives) to help their own console as much as Sony's.
So how do you think will really happen here? Where will the bulk of the GTA4 sales go? Will its last gen fans bite the bullet and grab a PS3 (priced $200-300 more than the PS2 when GTA3 came out)? Will they jump Sony's ship for the 360? Or will they simply wait for another PS3 drop (or two) next year?