Starbuck meets a piano player in the bar where that she eventually befriends. We later learn the character is in her head and it was her father. There were great flashbacks to when Starbuck was young and we finally got to see a good Starbuck story. When she plays all along the watchtower at the end, it is unexpected and really leads us to tying it all together for the finale.
Boomer came back and really showed she went to the dark side. She drew Tyrol into helping her by having him remember his feelings for her to help her escape. We learned of a new ability cylons have to project thoughts into each other's minds. I don't believe this reveal was a one time thing and may explain quite alot about the visions some of the characters had throughout the series.
Boomer having sex with Helo and then stealing Hera and deliberately jumping close to the ship really had her as a one woman wrecking crew. It looks like Galactica is done for now. (it is open to debate if she really had it in her mind to seduce Helo or if she went along with it because she assumed Athena's identity and to refuse would be inconsistent with that)
It is open to debate how much she played Tyrol or if she really meant the things she said. Him going to the house at the end and finding their kids bed empty was really well done.
It looks like things are about to all come together as there are only three episodes left. They are ending on top!