My Vita TV showed up earlier this morning. Aside mentioned in the OP, NA accounts won't but I have a JP account for various things anyway.
It straight up has English support for the interface, so that's handy if you can't read Japanese.
I haven't tried much yet, but I downloaded Soul Sacrifice (jp ver) and played a fair bit of it, feels great with a proper controller. They use L2/R2 to simulate touching the screen but I believe that is specific to SS since the touch stuff is pretty limited (there is more complex touch when you are dead and in soul form in multi player, didn't die so I have no idea how they changed it)
If anyone has any specific questions I'd be happy to poke around in it and answer as best I can.