Thanks to USA Today, Yahoo, /Film, TFW2005 and Transformers Movie Chronicles, I can bring you a list of important Autobots and Decepticons as Michael Bay begins to roll out his cast for Transformers: Revenge Of The Fallen.

Not mentioned here are other characters we know to exist, like Dune Buggy or Chromia, another possibly female Transformer. However, this is the first we’ve heard of The Doctor (though I think this robot isn’t actually called that) and hints that Ravage has a part to play…

Optimus Prime: The Autobots’ leader, Peterbilt truck. [PIC]
Ironhide: Weapons specialist, GMC Topkick. [PIC]
Ratchet: Medic, Hummer H2.
Bumblebee: Friend to Sam Witwicky, 2010 Chevorlet Camaro. [PIC]

Arcee: A female Autobot, Megan Fox’s hot-pink motorcycle. [PIC]
Jetfire: A fighter plane crash-landed on Earth a long time ago, SR-71 Blackbird. “He’s old, craggy, forgetful … doesn’t work very well. Can’t transform very well, because he’s very geriatric. They get stuck with him a lot,” Bay says. “He knows the plan of the bad guys, but he forgets all the good parts of the plan.” [PIC]
Sideswipe:  General Motor’s silver Corvette Stingray concept car. [PIC]
Jolt: the original toy was a Decepticon but not in this movie, Chevrolet Volt plug-in hybrid.
Skid & Mudflap: a.k.a. “The Twins” - Chevrolet Beat and Trax concept cars. “Some of the junior Transformers are just dumb,” Bay says with a laugh. “But it’s great for kids because they’re like the Little Engine That Could. They’re (screw)-ups, but they get really heroic at the end.” [PIC]

Starscream: Formerly Megatron’s second in command, F-22 Raptor jet. [PIC]
Scorponok: The mechanical scorpion that attacked the American troops in the desert.
The Fallen: An ancient robot, sort of the Transformers’ version of Lucifer. He’s one of the original robot aliens, and his defiance and arrogance led to his banishment into another dimension. The screenwriters call him “the most elemental bad guy” and say that The Fallen holds the key to life on both Earth and Cybertron, the Transformers’ home planet. [PIC]
Sideways: The Audi R8 seen crashing through a building in the trailer. [PIC]
Soundwave: A cassette player in the original toys. An evil communications expert, an orbiting space satellite. [PIC]
Ravage: The ultimate spy. A four-legged, cat-like robot. Ravage doesn’t turn into anything. “In the spirit of ‘more than meets the eye,’ Ravage isn’t just lethal because of his sharp teeth,” says screenwriter Alex Kurtzman. “There’s actually another skill set Ravage has that didn’t exist before, so there’s going to be a surprise for fans.” He doesn’t talk like the other Transformers. [PIC]

The Doctor: A spider-like droid that transforms into various implements of torture. (Dave: I heard this guy was called Scalpel) [PIC] [PIC]
Wheelie: A small, radio-controlled truck.
Demolisher: One of the Constructicons that transform into construction vehicles. [PIC]
Devastator: A giant robot formed by the Constructicons joining together; individually, they are: Scavenger, Scrapper, Hightower, Longhaul, Rampage, Overload and Mixmaster.  Michael Bay says that when Steven Spielberg saw Devastator, he said “This is (expletive) awesome!’ ” Bay says, “It’s always nice when you can make him swear.” [PIC]
Megatron (unannounced) [PIC]