I'm kinda thinking that Optimus will die is Revenge of the Fallen and I think he will be killed off for the exact same reason he was killed off in the G1 movie... to make room for more new characters and toys.
I think it's pretty unlikely that most people will buy a 3rd Voyager or Leader class Prime. I don't think that there could be enough difference in a 3rd set of toys to make people buy them yet again, especially voyager Prime.
I imagine we'll see Ultra Magnus and/or Rodimus in the 3rd movie and Ultra Magnus would make a good Leader class figure to replace Optimus.
So far the rumors are that Jetfire is an old Transformer whom walks with a cane. He and Prime will probably both be killed. I just don't think Jetfire will be a character needed for the 3rd movie, especially since he combines with Optimus.
Revenge of the Fallen seems to be a darker movie and more than likely the Autobots are gonna get served. I imagine we will see more than just a couple autobots get killed in this movie. In fact I wouldn't be surprised if Ironhide and Ratchet were both killed because it doesn't seem to make since for them to be in a third movie when there are many, many more characters we would all like to see make it to the BIG screen...
Also... I bet Starscream gets blown away by Megatron/Galvatron
Bumblebee will be the only character from the 1st movie to survive to the 3rd movie... just my thoughts

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