Just loaded Phiremod v7.1 on my Nook color and I must say that I'm impressed.  It's fast, clean, and looks wonderful!  Based on CM7.1, it reports itself as being Gingerbread 2.3.7.  I'll post a HOWTO later as I don't have the time to do so right now.  But, here is a screenshot of my Nook, running Zeam launcher instead of the included Launcher Pro.  I'll also post a review of it after I've had a few days to play with it.