This is the flashback episode that has been discussed on the forum over the past two or three months. Most of the scenes in the episode are flashbacks from the "lost year" that was skipped over in the Season Two finale.
Boxing plays a large part in the episode. It looks like it was influenced by Cinderella Man and Million Dollar Baby, but that's just a guess.
A note to track and steling: This is the episode I was talking about before. I don't know how brutal the scene is but there will be a particularly violent fight between Lee and Kara.
NOTE-BSG is taking a week off because of the Thanksgiving holiday. Tune in 2 weeks from now for "Unfinished Business."