I was thinking to myself, Optimus Prime, Megatron and Sam have all interacted directly with the AllSpark in some way. Now the following will be a bit confusing unless you differentiate the AllSpark (the afterlife containing the sum of all Transformer knowledge) from the Cube (where sparks and energon enter the physical world) as I do. * Megatron had the Cube (and later a remaining shard) crammed through him. Rather than sending him in stasis lock so he would incubate new energon powers as we all speculated, the effect was really '100 cups of coffee kill, 1 cup's ok'. It didn't seem like he gained any knowledge too, since The Fallen was there to explain the secret history of the Transformers. * Sam became a vessel for the AllSpark after touching the shard in his jacket, and received its knowledge as well as being able to commune with the sparks within (they were annoying symbols when he was alive, but the connection was much better when he died/was on the verge). * Optimus was stabbed with the Matrix, which in early drafts of the script and the novelization, was clarified as being another AllSpark relic that was created by the Cube for the Primes to power the harvester. The Matrix must have given Optimus its knowledge since he suddenly knows who The Fallen is (unless he gained this information while his spark had gone into the AllSpark). So all three of him have had a physical connection with the AllSpark. How could the writers exploit this for a third film? Could Optimus and Megatron gain a deep psychic connection, allowing them to sense each others' emotions and use this when planning their attacks? Would their minds overwhelm Sam to the point he would have to become a Powermaster? Could Sam be used as a camera (I'm still advocating he get captured by the Decepticons in TF3 so they can have more screentime)? What if a third party (eg. Nova Prime) used this connection to enslave them?
Hate to break your creativity but... no. My guess is that since Prime and Megatron are inorganic, they weren't effected like Sam was. Prime either knew about the Fallen and wasn't telling anyone, found out after he died or gained the information when he merged with Jetfire's corpse. jD001