Last week Android developers managed to bypass the encrypted Bootloader that was preventing people from augmenting the Barnes and Noble Nook Tablet. This set the stage for people to load in the latest iteration of the Google Android OS, Ice Cream Sandwich.
Some enterprising young users have managed to get CyanogenMod 9 to work on the Nook Tablet, giving you a full unbridled Google experience. This is beneficial for users who want to ditch the heavily modified version of Android that Barnes and Noble has crafted to give their e-reader a distinctive appearance.
The essence of the new method to get Ice Cream Sandwich on the Nook Tablet is to allow the device to bootup from an MicroSD card with the new OS on it. This is great for the average user because you can load your unit up with one operating system and install whatever apps you want and then merely take the card out to get the original B&N experience. I agree with this way of approaching things because it lets your average user experiment with a very low-cost tablet by using the new OS that everyone is talking about, and then go back to the way things were without the headaches. Normally, the one thing stopping people from rooting or changing the operating system is the inability to use the Nook as it was intended.
The developers of the CyanogenMod 9 program for the Nook Tablet are working feverishly on the final build that should be public-ready soon.