I got the feeling that this meeting was the first time Gin and Aizen met. and the officer killing was Gin's own intiative, and not by plan...
it's good to see Byakuya not acting like a complete jerk, meybe there's hope for him yet.
the guy who doesn't want to be a lietuenent is Kaien, right? Rukia's dead\espeda captain, or is it someone else?