NookDevs have already teared down the nook and found the components, the list is here:
http://nookdevs.com/Teardown
Also, I think its actually a mixture of Android/Linux coding, I don't quite know. Found the following information from the Teardown regarding it:
"Software
Appears to be running a generic Android image with B&N customization on top to hide the Android underpinnings
Android 1.5 Cupcake
Built Tue Dec 1 14:50:20 CST 2009
Linux 2.6.27
turboboot and u-boot boot loaders
asound
pvplayer
ALSA 1.0.18a"
Read more:
http://nookdevs.com/Teardown#ixzz0zDWgh5ti
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