Game compatibility list?

One main problem is that many SONY provided lists will be region-specific. It's extremely difficult to be certain that any list is fully complete or current.

I would assume the most complete list would be available on the Japanese Playstation site, but you'd probably want to run that through some google translate or the like. I'm unclear on the compatibility of titles between regions (ie. taking a game from one region and using it in a vita tv from a different region) so I'm not sure if this helps you (as you've not specified a region), but whether that works could be a separate question anyways. If games are supported across regions, that makes a complete list even harder to pin down as it would require trying all games from all regions in order to be complete.

Vita TV would seem to be region specific. I own a north american "Playstation TV" and Hyper Dimention Neptunia re:birth 1 isn't compatible as of launch.

I have been able to confirm a few that I own. I have The Japan physical versions of Phantasy Star Nova and Sengoku Musou Chronicle 3(Samurai Warriors Chronicle 3) and the English International version of Resident Evil Revelations 2 from Asia, these all play fine on my American Playstation TV.