This is just the new name for the Gaikai service they purchased ages ago. It's sort of the Netflix of video games, or will be, I guess. It will allow for the streaming of games from PS3, PS2, etc., on Vita, PS4, tablets, and smartphones.
Granted many (most?) of the games won't be optimal for playing on tablets/smartphones, but that's only one aspect of the service. Also, once better iOS7 and Android controllers hit (and don't suck), it'll probably be much more appealing.