So, what happens with the Matrix of Leadership at the end of TF2? Does it get distroyed with the Energon machine in the Pyramid? Or perhaps Optimus keeps it from himself (after all, how did we know there would be a second sliver of all-spark in Transformers: ROTF?).
I hope it is still out there in the story, that would possibly open the door for Unicron and others in the future. However, I guess it gets distroyed.