I heard/read that Bumblebee wasn't included because Volkswagen didn't want to have it's image to be associated with 'machines of war'. Odd since, if I'm not mistaken, Hitler was the one that originally commissioned the beetle.
The Transformer teaser, from what I hear, will be included with Pirates of the Caribbean 2. Saw Superman Returns (oh shit!!!) last night and it wasn't in it. -how dope was the Spidey teaser btw!?