Ellen Tigh comes back and is quickly consumed with jealousy over Tigh's relationship with the six. After showing a quite differenty side to her character in the last episode, she quickly slid back to the ellen everyone loves to hate.
Six loses the baby, but it seems to be more of an emotional cause of the stress of seeing Tigh torn apart by ellen than it is because a cylon child is not possible.
The cylons were close to leaving and jumping away. But the loss of the baby probably ends that. It was surprising to see Tyrol vote to leave so quickly. One would think he would be the one conflicted since he got along with everyone the best and was made chief again. Ellen was the swing vote but was too consumed with her own problems to care very much.
Balter finally has something to do in the new season as he is actual becoming more and more of a real human being. His scene with Laura and Adama where they actually take him seriously (after some back and forth) brings his character full circle to the beginning of the series when he was the respected scientist. Now he is becoming the respected religous leader.