well the ps3 has been out for 155 weeks and has sold 25,743,746 at the same time the 360 had sold 22,249,757 thats a differance of 3,493,989 thats 22,561 a week extra on average more are sold, so 310 weeks if averages carry on,
but i think christmas the ps3 will sell lots more than the 360, i been asking people what there getting there kids for christmas, most say the ps3 or wii, and the reason they choose the ps3 over the 360 is they want a blu-ray player so there rolling it in to one, and with rumors the live price is going up that put a few off, they like the free online gaming of the ps3
these are my thoughs, i know the 360 fans will laugh and scorn but thats cause they know im right, lol