Excellent episode. I've been following this show from the beginning (never read the comics) and own season 1 on blu-ray.
My favorite part had to be the debut of Michonne. That just intrigued the hell out of me; I was like, "What the hell is this thing!?", and then I heard them on Talking Dead where they explained a little more about her.
Definitely one of the best shows on TV and season 3 can't come soon enough.