I don't want to be a total ass, but reports are stating its the PS3 thats having issues
http://www.computerandvideogames.com/article.php?id=187902
http://www.gamezine.co.uk/news/game-types/shooter/ps3-owners-report-freezing-errors-on-gta-iv-$1220708.htm
I just quickly googled GTA and Freezing and those are the two news articles that popped up about the issue. Mind you its 7:50am and maybe the 360 articles will come out at some point later today.
Looking at the xbox.com forums and the few (I only saw two on the first two pages) describe RRoD's about to happen and not random fatal errors.
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