Thanks for the color code tip in Mail. I didn't dig deep enough to see that. Unfortunately, the way I'd want to use color coding would be like this...in Address Book (and thus Mail) I'd like to be able to set color groups like (friends, prospects, clients, family, etc.) and then assign those colors right in AB on the fly. Then within Mail I could choose things like "Send to Family". Yes, I can make groups, but that's not as convenient or easy to to remember to maintain as colors. With one look you could see if a color has been assigned or not, with groups, you have to manually read through the entire group to see if you forgot anybody.
Thanks for the tip though, I can think of ways to use that.