I'm a little surprised no one has posted anything about the season finale. Here's my thoughts. Spoilers, of course.
I stopped watching Under the Dome when CBS and Time Warner had their recent spat. I read a recap of the penultimate episode so figured I would watch the finale. Despite having missed a large chunk of the season I had no problem following the main plot (I'm not sure if that's good or bad).
Barbie is falsely accused of murder and attempted murder (someone I never saw showed up for a few episodes then died) but Big Jim is the real bad guy in town. There's the egg, the little dome and the butterfly. The Water Man is gone so I'm assuming Big Jim took care of him (it doesn't seem to be particularly important exactly what happened).
The bit with the Other in the form of Mom with Glasses made me think of one of those episodes of The Outer Limits (the newer version) where aliens help a select group of humans to survive an impending catastrophe. If everything outside the Dome ends up devastated I called it.
I would rate Under the Dome above Falling Skies for summer sci fi viewing so I'll probably watch the next season.