Word in the grape vine is that there is going to be a Transformers 4 & 5. As an avid Transformers fan who hated the last two Transformers films and only mildly liked the first, I am not enthused.
I would assume that the new series will bring in the Decepticon leader Galvatron and the planet-sized world devourer known as Unicron. I have very low expectations for such an undertaking as the pattern for the last 2 Transformers has been to make a number of Transformers look really cool:
Then kill them in a utterly humiliating and ultra fast way.
There is some hope for the movie in that there might be a new director and they may get rid of Shia Lebouf (which would be awesome). Being a fan, I'll inevitably watch both movies if they come out, but watch for a repeat of the same method:
Galvatron and Unicron will be made to look really cool and really powerful, then they will be defeated in about 30 seconds by Optimus Prime with little effort.
"These shall be your minions...."