The future of humanity is at stake and it's all up to this boy and his cube, with help from the muscle car, and in hopes of winning the heart of this girl. Not a new storyline, we all realize (OK well, maybe the cube part's a little different -- kinda Borgy -- but not the robots, although these ones are quite expert at disguising themselves by curling up).
The Pentagon was happy to show off its best toys, in this wash of eye candy. A broad cross section of kids, some adults, get a character with which to identify, plus many will see the car they want to drive, or truck, one of the many airplane options. Flatscreens galore. Department store bling. Lots of shopping ideas.
Was the whole point of that little dog to embed a link to Taco Bell? Lots of amped up brand name iconography, blended with other governmental, patriarchal, patriotic razzmatazz and symbols of authority (scenes of national security goons bossing USA homelanders were a focus in The Last Mimzy as well).
The autobots themselves might be cast as advertising something more abstract. How about the ability of capitalism -- the cult of imaginatively using one's head -- to morph endlessly, if sometimes only one-dimensionally.
Transformers is a loud nerve-jangling ride with lots of bovine growth hormone or testosterone or whatever that is. Amusement park stuff, cram packed with clichés. Enlist today. Serve your country.