For the record, I really loved Assassins Creed: Bloodlines for PSP. I think the same can be said about this game: A console quality game, on a handheld. And now, it can also be said, console quality graphics. They're amazing, and its the first thing that stands out. This game uses the same engine as its console counterpart, and it looks quite as stunning.
Now, the sound is a quite a bit off, its... not all too good sound design. There's not really ambient noise, and for an open world game, that's a bit odd. The other thing is, the over use of very old and almost cliche sound effects. Other than that, I have no complaints regarding technicalities.
Now, as for the story, I absolutely love it so far. The beginning was more than a little rocky, but once you got into it, it moved along nicely, and made you feel immersed. This is truly Assassins Creed as we all know and love, right in the palm of your hand. So, no real complaints there.
The multiplayer, however (Yes, it has multiplayer, which wasn't exactly announced), is quite... different. It uses the location data and pits Assassins against Abstergo agents, where there is a VAST overpopulation of Assassins, and Abstergo agents only seem to appear in the middle east and west Asia... Too much to explain, as I haven't delved deep enough, just know that Assassins Creed multiplayer is there, with a twist.
Now, for the new features. the Vita uses the touch screen, back touch panel, GPS, camera, and motion sensors. I have yet to use the latter two. The touch screen is used for various things, such as selecting weapons and enemies in a certain mode. The menus and such can be used with touch, and with the physical controls, which I much prefer. The back touch panel is for similar usage. The GPS is used for multiplayer, as well as the "near" functionality.
Also, if you have Assassins Creed III for PS3, if you connect the Vita to the PS3, then you can unlock certain bonuses for each game. I have yet to do this, as I have spent all the money I could on this game and NFS: Most Wanted. I'm a bit disappointed thought, that there was no Cross-Buy deal, but I guess I can understand; this and ACIII are entirely different games.
To wrap it up, with the nice addition of the muliplayer and "near" functionalities, Assassins Creed III: Liberation makes good use of the PS Vita and is to date, one of the best Vita games on the market.