I like the program icon, but I miss the colour-coding of the format icons (this is something I liked with ACDSee back on Windows, and that I wanted to preserve in Xee).
Xee has a mechanism to easily replace its icons - you can pack them in a bundle named .xeeicons, like so: http://wakaba.c3.cx/releases/mac/Default.xeeicons.zip. However, that doesn't include the status icons. I could pretty easily add support for that too, though. I'll try to get that done for 2.0.