Alice The Pretender
In the case of Alice, the shell will be an attractive human woman while the inner robot is best described as a hybrid of the Frenzy robot design from the first movie. The Pretender Transformer will have an arm that transforms into an energy weapon, a long tongue, and a scanning tentacle.
So what is a "Pretender"? It is a subsection of the Transformers line that was first introduced back in 1988 where a Transformer has a "synthetic organic outer shell" that hid the robot. Back then the shells where just a plastic shell that split in half revealing the TF inside which usually had a pretty crappy alt mode. Click here for the Wikipedia entry.
As for the character of Alice, currently the only confirmed information is she befriends the freshman Sam in college. I want to discount the rumor but really there am a whole lot of story left that we know nothing about so any theory on what part the character plays in the movie and for how long remain valid. The actress has not been spotted on any other sets except those shot in Princeton but that doesn't mean she did not show up for scenes filmed at the various air force bases around the country or overseas.
There is also a video of a scene shot in Princeton that supports this theory as it shows Lucas calmly walking away while extras are panicking around her suggesting something sinister is going on with the character. Could she be the form that "Ravage" hides in before chasing Shia, Megan and Leo on the streets of Princeton?
It is an interesting idea to say the least. While Pretenders were poorly executed back in the '80s it doesn't mean it couldn't work in a movie if handled well and judiciously. Really the only problem I have with the idea is it a little too Terminator like. If there wasn't a Terminator movie in production and a TV show, having a Pretender Transformer preying on our human heroes could almost be a movie unto itself. As it is, I am very skeptical.
Source: Transformers Live