Versus won't show up. They have no interest in the US market. Bandai doesn't see a large profit from the US PSP fanbase. Which is why they're not bringing RM2 either.
The only thing that might prove the opposite, is because...there is the thing that a US copyright for Vs. (and I believe Graces, too?) has already been filed.
Couple that with the notion that this game, whether one wants to admit it or not, is one that's meant to directly contend with a certain other "crossover fighter" starring another RPG franchise, and there's at least SOME hope for a US release release. After all, if Dissidia hits it off well with US PSP owners, that may only serve more of a reason for Bamco to want to try and get in on the act, too.
No guarantees, of course, but we can only wait and see. But any "serious" Tales fan would be ready to import any way. You miss out on too much good stuff like Tales of Destiny Remake: Director's Cut and Tales of Heart, if you do!