Well it looks like SO4 International won't make 80k first week (SO4 on 360 did 165k by comparison FW). Seeing as how SO4's preorder numbers are a good bit lower than Ar Tonelico III and that did 82k FW. It's just a matter of how much less than 80k that is unclear. The guys from that site, who have a better understanding of the numbers, estimate that SO4 Int may go sub-50k FW. Which would be abysmal.
Telling from the figures, it appears that ToV 360 owners were a lot more likely to double-dip than SO4 360 owners (because ToV's PS3 port was better than SO4's PS3 port)
And it appears that most Star Ocean fans went out and got SO4 for 360 (as well as the console if they didn't already have it) instead of waiting for a PS3 port. Whereas with Tales fans, a good number of them decided not to bite when it came to 360 and held out for a possible PS3 port instead (even back then, it was rumored that it would happen.) Or it could just be that word on the street in Japan is that Star Ocean 4 sucks (bad word of mouth as Soriku said) and so PS3 owners are avoiding the game.
I personally did not like SO4's gameplay but home console jrpgs have me pretty jaded so it's not like it was any worse than usual. But apparently a lot of people in the west thought SO4 sucked so it wouldn't surprise me if that was the same in Japan. The English VAs didn't bother me like it did everything though. I thought they were ok. Lymle (aka 'kay girl) is good for the lulz. That high-pitched kawaii desu ne stuff in the game though, KILL IT WITH FIRE! lol. But that kawaii desu ne type of voice is just as annoying in Japanese too. And you hear that kind of high-pitched kawaii voice in just about every other animu and uber-Japanese video game.