From the trailer, it looks like after getting his powers back, Sylar will be hunting the members of the Company in revenge. It also seems like, true to the season's title, there will be a plethora of villains. Noah Bennet's line that "These people are very dangerous. It's like twelve Sylars running loose" suggests that not only will there be at least twelve villains running around, but they will all be at Sylar's level of power and insanity. My theory: since the trailer shows lights flickering and things getting broken, I think that in attacking the Company, Sylar will end up releasing villains that were held in the Company's custody, similar to Peter and Adam last season.
I can't wait!
EDIT: There's actually two parts to the teaser. I posted both of them.
