Well, ofcorse there been the pressure from Sony, and it is completely understandable - GT5's main rival game on a rival system is releasing this year in the pre-holiday season. It's bound to get a certain amount of impatient ppl buy the rival console and enjoy the, maybe "less than perfect", racing sim, rather to wait another year (as I've understood GT5 is releasing in March for Japan, so probably next holiday season for the western markets).
GT5 and FFXIII, as two strongest PS IP's, have certainly destroyed a fair amount of Sony's sales with all the delays.

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