So here's what we know from the trailer...
* The major thrust of the season will involve the escape of 12 criminals from Level 5 - a prison within The Company used to hold the worst of the worst. 12 criminals all reportedly the equal of Sylar in power and psychosis.
* Expect lots of Sylar early on since - before the writer's strike - they shot a LOT of material with him so that he could still "be" in the show while he was shooting the Star Trek movie.
* Hiro will gain a new arch-enemy - a woman with super speed powers. Adam aka The Original Kensei from Season 2, will also be returning at some point looking for revenge.
* One of the first new episodes will involve an alternate future and show the deaths of most of the major Heroes. If the trailer is to be believed, Claire is one of killers or the killer.
* According to the gent who plays him, Nathan is not quite dead yet and will spend most of Season 3 working with Peter against their mom. No word on how he survived the end of Season 2 but the smart money is that they knew the attack was coming and faked his death.
* Future Hiro - or A future Hiro - will be returning.
* Kristen Bell WILL be coming back to play Elle. Not as a regular, but she will be a part of the action in one of the major story arcs.
* Niki survives, in a sense. Word is that Niki "dies" but that a new personality will be taking over. No word yet on if she'll be a hero or a villain.
* William Katt (aka The Greatest American Hero) will have a recurring role as a reporter who hounds Niki... or a woman that looks a lot like her.
* Bruce Boxleitner (aka Captain John F***ing Sheridan) will have a recurring role as a politician.
Yeah. Looking good.