AFAIK for Symphonia Nintendo helped for the localization, and owned something of that game in the West as a result.
Don't think anyone knows for sure if there was anything similar for Vesperia (it did come out almost simultaneously with Japan in the US, did MS help in a similar way?).
If there wasn't such a thing, I think Namco will bring it over, exclusivity period is obviously over for that game, only the localization remains.
P.S. What happened to the US xbox360 release anyway, there were hints that it was discontinued.







