jake_the_fake1 on 01 May 2008
perhaps developers chose to render at 640 and then upscale to 720 so they can achieve a sort of AA which reduces the jaggies but costs less performance wise than actually having 2xAA at 720p, and with the freed up processing power they had left, they used it for smart filters to help improve the IQ, maybe this is the method they chose to increase the IQ of the game and is why many reviewers tend to favour the PS3 graphics of GTA4.
