According to a report on NeoGAF, the latest Game Informer contains a preview of a Vita-only Assassin's Creed game called Assassin's Creed III: Liberation.
It's unconfirmed, but other GAF users are also saying they read the preview. Among salient facts about the game: It will star a female assassin named Aveline, will take place in New Orleans (yes!) during the same time period as Assassin's Creed III, will have multiplayer, and won't feature Desmond. Aveline will meet Connor from Assassin's Creed III, and her mentor will be an escaped slave, which combined with the location and time period could mean that "Liberation" could refer to the liberation of American slaves. Oh, and it will feature alligators! Awesome.
That image up top is of Shao Jun, the woman assassin in the short film Assassin's Creed Embers. I've been wanting a female assassin to turn up since seeing that; sounds like we'll be getting our wish.