So, I got a Nook for Christmas. Well, we got a Nook. (I have a feeling this is rapidly going to be 'we have two Nooks').
I'm going to pass on something the average person might not notice. Once you register your nook, it automatically sends purchases, with no further confirmation, to the credit card linked to your B&N account.
The way the default settings are, anyone (like your children, for example) could buy books on your Nook and they would automatically charge your credit card. And, unlike Amazon, B&N does not allow you to return ebooks.
Please, if you have a Nook, go into device settings, then shop, then check 'Require password for purchases'. Especially if you have kids...or are a bit of a klutz and might accidentally buy something while browsing (it requires two clicks, but I've had my hair touch the Nook screen and click on something more than once...oops). Much easier than trying to clean up an unauthorized purchase mess later.