Well it certainly has an efect on the Xbox, the sales are rising in Japan. In the west? Barely an effect at all, only FF XIII has some effect (people that no longer need to buy a PS3 for the game).
What's bad about this? All the big RPG series are loosing sales, and quite some. ToV is one of the worst selling games in the series, so will SO 4 be. It isn't a problem, they received money from MS which compensates for the low sales. But, MS won't keep buying their timed exclusivity forever, which is very bad for the RPG genre.
But, they are very successful on 'boycotting' the PS3. If the PS3 had all those RPG's, it would be selling a lot more in Japan;







