YouTube phillyfilmgirl, responsible for some of the recent videos from the set of the second live action Transformers Movie, Transformers: Revenge of the Fallen, has posted what she reports is some of the plot information over on TFW2005.

Scroll down to read the spoilers:

"heres the whole story of why he read the book so fast IN the video i posted
-he gets some sort of a box, he touches it, it zaps him
-all of a sudden in class (which is a large lecture hall) he goes crazy saying whats wrong in the book and drawing symbols all over his notes and on the board
-i myself have held and seen the astronomy book, its pretty big
-he calls mikaela freaked out, thats where the video comes in
-from there, he tells her on the phone in another location, 'dont touch the box' so i guess thats what did it to him
-then he draws a lot of symbols and i guess it leads him to the final battle and drawing symbols

he also meets another girl, alice who turns out to be evil and is trying to get all up on him at a party, bumblebee crashes the party and here is the conversation sam has with a frat brother
"hey freshmen!" frat bro
"yea?" sam
"is that ur car parked there?"
"what car?"
"the yellow one on the bushes"
"oh my friend just went to get u a tighter shirt"
"there is no tighter shirt i checked and you dont have any friends...say how about if i park my foot up ur ass!"
"what size shoe are you?"
"10"
sam then stumbles on some bushes outside the party, gets in the car with alice (that girl i mentioned) bumblebee doesnt like her (hence that video with the spinning stop we saw), she gets out with goo on her because of bumblebee then later alice is seen in a courtyard all meniacle looking after some sort of explosion and the trio are running from her.  oh yea, he gets a new roomate at college and his name is leo - leo knows or figures out about transformers and they basically kill that new saturn...i think it gets split in two and placed up high on a ledge in a warehouse/factory place, and theres explosions thats some of what i know happens, hope that helps, this is all the truth.  the parents are in france...something bad happens there they all observe a tv in a open air market and people are crying (an old woman is even wearing a biret), a building collapses, and people are fleeing from it and then we see a transformer in france hunting down the parents or protecting them, i dont know.   shia gets strangled by megatron too...we will see megatron's hand strangle him"