Why is it so important to call him "Spike"? They're not the same characters!  

 

The novel goes into much more detail I suggest you read it....the matix is lodged into prime and it now has the power of the allspark....When sam picked up the cube splinter the allspark used him basically as its house...Jetfires speech during the movie describes the allspark as something that can never be destroyed...it is not an object so it was passed onto sam and then when sam picked up the matrix all the knowledge he had & the power of the allspark was transfered into the matrix...prime has it now

 

After coming into contact with vector sigma he becomes a sari like charecter

 

becuase that makes him "yet another Witwicky" give ti another couple decades and Mr. and Mrs. witwicky will have more kids running around than the brady bunch

 

Isn't the matrix buried under a pyramid??? Or was that just a shell??

The ambassador thing honestly doesn't work for me. There is just too much bureaucracy in our world to ever allow a 20 something year old kid to have contact with an alien race. The Autobots follow Prime and Prime will conceded to whatever the government wants because it is against his beliefs to force them. With the autobots now exposed to the world it seams likely the autobots would be deeply entangled with the government. I see Sam getting the life he wanted and being left alone to live his life and banned from seeing the Autobots.

With the autobots so secure Sam would become a likely victim for the decepticons to prey on. I say have him captured in the opening scene and taken to the nemesis. Have the decepticons demand the autobots fight them on their terms. Sam could spend the whole movie as their prisoner and learning more about the cons. Let lennox and epps be the main characters this time. Just a thought anyways

 

Its gonna be tough to not be just repeating the same thing like a hmmmm saturday morning cartoon :S
I reckon they or you lol could put Sam as not so much an ambassador for the transformers but a good influence in them staying, even though it wont work... I'd love for the president to still go with teh idea of asking them to leave earth, maybe allow them to live on the moon (moon base 1) if they feel they must be close to the earth and then the decepticons can attack and could hold earth hostage, and then maybe have some mini story of sam rescuing a bunch of people, like in terminator bein stuck in skynet

 

just a shell....

although I do wish I could minimize Sam's role in the movie and have lennox & be Epps be the stars...it isn't possible...Sam needs to be involved in the plot of the story...Honestly i like Shia Labeouf & the character, I think he is the funniest character in both films...And as for being an ambassador i really wouldn't call it that...but im not gunna get into details..thanks for the input