My impression from the designers was that no new factions. This is a Rebel vs Imperial game, and that is how they balance the game. And I doubt they are going near the NJO era, especially with its existence in doubt.
I know they have said this, but tournaments have already ended up having Rebel vs Rebel and Imperial vs Imperial matchups. And there are only so many of the cool ships they can shoe horn into one side or another. A Pirate/Black Sun/Consortium faction would make a lot of sense, even if quite a few of their ships could be use by one side or another.
We can hope they come to their senses. There is definitely enough interest on this board or others to suggest that people would like a 3rd faction. It comes up at least once or twice every week.
There are other things they said they wouldn't do that they did anyway. I think it's possible we'll see more factions at some point.