Optimus Prime: Not only is he the leader of the Autobots, Optimus Prime is also a kick-butt Peterbilt 379EX long-haul semi-truck to boot. He's been the star of pretty much every incarnation of the Transformers since its inception.

Ironhide: A one-time bodyguard, and Optimus' oldest friend, Ironhide is a black 2007 GMC Topkick C4500 in the movies. An Autobot weapons specialist, he's been with Optimus Prime from the beginning and has undergone many incarnations in the toys, cartoons, and comics. One thing that has remained the same throughout is his reputation as a fierce warrior and fighter.

Ratchet: A yellow search-and-rescue Hummer H2 in the first movie, Ratchet is the Autobot medic and has been updated to a 2009 Hummer H3. According to creator Bob Budiansky, Ratchet was named after Nurse Ratchet from One Flew Over the Cuckoo's Nest. Let's hope he's more gentle with his patients than she was.

Bumblebee: Sam Witwicky's yellow 2010 Chevy Camaro (Sport Version) and an Autobot bodyguard. Bumblebee was the first Transformer to befriend Sam in the 2007 movie and is voiced by Mark Ryan, although Bumblebee's voice has been malfunctioning ever since his meteoric landing on earth, causing him to use radio sound-bites for communication.

Jetfire: As in the original, this fighter plane crash-landed on Earth a long time ago will become a reformed Decepticon fighting for the humans. His alternate form is an SR-71 Blackbird, the outdated-but-still-sleek Cold War spy plane.

Sideswipe: A candy-apple red Lamborghini in the original, Sideswipe joins the cast this time as General Motors' silver Corvette Stingray concept-car.

Jolt: A new foot soldier unique to the movies, Jolt is played in four-wheel form by the Chevy Volt — a forthcoming hybrid plug-in. Being an electric car, his weapons are (no surprise) a pair of formidable electric whips. Although a last-minute addition, and obvious product placement by General Motors, our sources say that the moviemakers are pretty pleased with the new character.

Skids and Mudflap: Two of GM's other concept cars play "The Twins," also known as Skids and Mudflap. These hip Autobot infiltrators transform respectively into a red Chevrolet Trax and green Chevy Beat. The cars come equipped with hyper-personalities and have the ability to combine. They will be opening the movie as a pink and white ice cream van and we're told that at some point they will form an even bigger robot.

Arcee: The only female Autobot turns up as Megan Fox's hot-pink motorcycle. Screenwriters Alex Kurtzman and Roberto Orci claim she was in an early draft of the first movie, saying, "We felt we needed to win the audience over before asking for that suspension of disbelief: a feminine alien robot."