I don't think I'll watch it. I HATED Admiral Cain, and just wanted her to die pretty much from the moment she opened her mouth. I watched the first 2 episodes of season 4, and I'm not lost, so like people said it doesn't seem to be required, and I just have no desire to watch anything connected to Admiral Cain again. Honestly, Season 4 is getting kind of tough to watch as it is. It has some very interesting ideas, but I've been done with everything gaius baltar since
I'm still liking a good amount of stuff in this show, but season 4 feels like it will be rocky enough without me wearing out all of my patience trying to sit through a long movie with a character i don't just dislike, but downright loathe, and a storyline that I hated when it was actually in the main series (a fleet admiral basically going so crazy The Joker would be telling her she needs a psychiatrist).