When I watched the anime, I remember being so
upset at what happens to Aizen in this volume. Now I can't believe I liked the guy, but that's a testament to the power of the characters, and the plot, I think. The author does a very good job of making Aizen likeable and sympathetic, and making Gin out to be the main enemy, with very little proof for the reader/viewer beyond "he's really weird and smiles a lot."
I love Zaraki, and in this volume he begins his battle with Ichigo. I can't help but be interested in the fact that a guy so wrapped up in his own power, who loves fighting and battles, who can presumably see how much knowledge of one's zanpaktou can assist in such fights and how bankai can amplify one's power, would resist or ignore the call of his sword. Plus, I feel bad for the sword.