Some knowledgeable folks over at Beyond3D have found that the X-Box 360 version of GTA IV runs at a resolution of 720p (1280├--720), but the PS3 version only runs at 630p (1120├--630).
To quote Quaz51: Regardless PS3 media look better for me, the light and atmosphere is more real (maybe HDR vs X360 MDR, post-process...)
A game store employee reiterates stating: Played both versions in the game store last night where I work, both on 720p HDMI (PS3 HDMI output 1.3b, X-Box 360 HDMI output 1.2).
The PS3 version is smoother/better visually in my eyes, 360 had pop-up issues. Conclusion: PS3 installs to HDD, which everyone knows its faster than DVD9 disc.
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