Lots of stuff happening in the first episode of the second half of the season:
Jason refuses to butcher the Rebels and their families, gets in to a fight with Dad and gets his ass beaten. Neville tells Monroe his son is dead. I think that will come to bite Neville in the ass later with Monroe. Even though Charlie turned him away I'm sure that sooner or later he'll join up with the rebellion.
Randall teams up with Monroe. What exactly is the Tower and it's purpose? Now that the amplifier is destroyed Monroe will need to get power up and running again. There was just the one that Rachel built, right?
Of course the big thing was Danny dying heroically. What was that thing that his mother removed from his body? I'm guessing it had something to do with his childhood operation. Or aliens did it.
I was pretty shocked that Danny was killed off especially since the first half of the season was all about rescuing him. On the one hand it makes the first 10 episodes feel wasted but on the other hand it provides a huge reason for Charlie, Miles, Rachel and Aaron to take the fight to Monroe. It gives them a more personal stake in it other than just wanting to stop Monroe. Now they'll never give up no matter how bad things get.
One other thing. It's pretty obvious that Miles and Rachel have a romantic past with each other. A lot of people are theorizing that Miles is actually Charlie's father. I wouldn't be surprised if they went that route. Revolution does like it's cliches.
Maybe I shouldn't be so surprised that Danny was killed off since that seems to be Kripke's MO. For the entire first season of Supernatural Sam and Dean were looking for their missing Dad and they reunited with him near the end. however just a few episodes into season 2 their father was killed off. So basically Revolution did the same thing just on a quicker scale.
The little girl who played young Charlie looked a lot like a younger Tracy Spiradakos. Good find there.