I have seen the description of Age of Extinction's Galvatron (the human-made Decepticon Optimus was fighting with before he was captured by Lockdown) from Hasbro.com that reads "The Autobots won a great victory when Optimus Prime defeated Megatron at the Battle of Chicago. Megatron is gone, but a new evil has taken his place. Humans have built a bot designed to be even more powerful than the fallen Decepticon leader. Now, the Autobots must defeat the mighty Galvatron!"
It leaves me to say this, but I hope that this means that like in the original Transformers cartoon, Galvatron DOES have an apparent connection with Optimus' arch-rival even if he somehow doesn't act like the Megatron we know!
I don't know if it's really gonna be portrayed in the movie, according to the Kreon Galvatron Factory Battle, some say that this is probably where Galvatron would become sentient (regaining Megatron's consciousness?) and turn against on the humans that created him and lead the Decepticons to conquest once more. This might be an excellent redemption for Megatron/Galvatron (following his downgraded portrayal in TF 2-3) after everyone enjoyed the megalomaniacal Decepticon leader back at the TF Ride in Universal Studios Hollywood/Orlando! Maybe Hugo Weaving should NOT be the voice of Galvatron if he doesn't enjoy his time providing his role as Megatron for all 3 TF films. I think Frank Welker (raspy voice or not, see TF Prime -- he almost sound like Hugo Weaving (without the Agent Smith accent)!) should be the voice of Galvatron (again but without the G1 counterpart's insanity)! But Michael Bay better not have Galvatron die for the 3rd (?) time and have him make out of the Battle of Hong Kong alive! He should know that there's a slight possibility that TF4 is only the beginning (for this new trilogy, of course) and not the end since DOTM!