Apparently, nook has been rooted. For those unfamiliar with the term, it means hacked. nook runs Google's Android phone operating system. I'm not sure which version. I think 1.5. iPhones are jailbroken, and Adroid devices are rooted. Like I said, all it means is they've been hacked.
What does this mean? For those who have to be on the cutting edge, it means that there may soon be applications to run on nook. The article even mentions the possibility of tethering thanks to the built-in 3G wireless.