Just got back from theaters watching this. I have to say, I have mixed feelings about this movie. It isn't the worse one, but it isn't so great either. They toned down the jokes a bit in this one. But if it is indeed Bay's last film, I can tell he's trying something here, although, not great. Some of the Autobots and Decepticons get very little screen time. Some more prominently than the others.
I love Frank Welker's voice back as Megatron. Good times. Also I think the movie did hinted Unicron. But I am not sure.
Overall, I enjoyed the ride. Hopefully it can be re-booted in which it pays closer to the G1 material.