There is not a single game that has been released up to now that will perform well. Not one.
They're either more suited to Western tastes or watered down versions of PS3 games.
The lack of TV advertising is a problem too, I am still yet to see to one!
Tsutaya in Shibuya (my most frequented Tsutaya) has dedicated most of it's back wall to the Vita, but it doesn't seem to be getting all that much interest other than nerds hogging the demo model.
The Vita desperately needs some better software, the current line-up isn't all that appealing. People don't want a portable PS3. Until there are games that fully take advantage of the rear panel, I can't see demand increasing. The marketing is quite lame as well, your average Joe doesn't know that it has a touch screen and rear touch panel, it seems that Sony just assumes people know all about it already.
I'm on vacation in England for a couple of weeks, but I'll probably pick a Vita up when I go back to Japan - but that's because I'm a gamer nerd. Can't see it being a mainstream success at the moment, some serious changes in marketing need to be made.