Forsaken?

Q u o t e:
So from the trailer it looks like the forsaken are showing their true colors. Soooo does this mean eventually the forsaken will no longer be on the horde with maybe other new factions?

Every society has their sub-sections that may or may not follow the letter of the law that their leaders set out there. In the case of the Forsaken, there was a bit of trouble that gets dealt with, but has some interesting repercussions for the entirety of the race.

If you haven't done the entire questline, I'd suggest you do so. You'll find it very enlightening.