Over on XDA the tablet has been rooted. Google Market has also been successfully installed (same method as Kindle Fire).
http://forum.xda-developers.com/show....php?t=1354487
Sounds like development of ROMs like C7 and ICS will still be very problematic given B&N's decision to lock the bootloader, but I'm sure it's only a matter of time.
I actually took my Nook back yesterday, but am glad to see this will be an option for whoever gets it as a refurb
Really is a nice machine. Really feel like B&N made a mistake locking it.