You may not know this, but all games need to be refreshed before the Vita can ‘see’ them via the Content Manager application. What this involves is close to black magic, but it’s already in action.
The first confirmed game is Grand Theft Auto: Liberty City Stories on the Italian PSN Store (from GAF) but big Peter here has also let me know that Gran Turismo, Chinatown Wars and Gravity Crash
are also working are a bit sketchy. Chinatown doesn’t copy over.
LittleBigPlanet currently doesn’t work.
If you imported a Vita and are currently running on a non-EU account, maybe now’s the time to switch? You’ll need to re-download them and leave them as bubbles.