Hi guys, I'm the author of that app. You can choose which format you want to save by default (hex or rgb) as well as hiding the color preview in the menubar through the app preferences. Please let me know if you feel like something is missing.
I've just stumbled upon two:
1. when mouse cursor approaches top edge of the screen, preview stretches vertically so that it's still square, but pixels are twice as tall as they are thick. That's on an mbp5,5 running 10.7.1.
2. Cmd+Shift+p uses physical location of p key disregarding programmatically set keyboard layout. I've only noticed because I'm using Colemak.