Samurai & Dragons was a recently announced title by Sega for the Playstation Vita, slated for release sometime this year. While it is only a short 30 second trailer, it gives you a look at some of the systems incorporated into the game such as a 4 character parties (I assume up to four players in multiplayer), a third person action-RPG battle system, some form of card system, the ability to build your own town in which you can conquer or interact with surrounding regions and a very enthusiastic narrator (Of course, there is a good likelihood the narrator is just for this trailer).
The official website HERE has also been updated with information relating to the characters and leaving many sections open for future updates. There is no word on if Sega will be releasing this game outside of Japan at the moment – but given how it looks from my perspective I would say there is a good chance of seeing it released eventually.