Gin Ichimaru remains to be super creepy.

Spoiler

He (allegedly) framed Toshiro so Momo would fight him. Toshiro meanwhile has an awesome water-ice zanpaku-to move.

Kaien's story was sad, but I liked the quote that there are battles to protect life and there are battles to protect honor. A lot of shonen series have this concept, but I understood it the most here.

Spoiler

Also Rukia's execution was moved to ONE day! Ichigo is powerful, but I'm not sure if he can help especially against whatever Gin has planned.

Random Thoughts:
Matsumoto seems to know Gin well(humanizes him a bit).
Byakuya Kuchiki seems like a heartless bastard.