The NC has an excellent display panel (7" IPS multi-touch capacitive 1024 x 600) coupled with a solid processor (TI OMAP3621 ARM Cortex A8 @ 800MHz) and running Android 2.1 with a promised upgrade to 2.2 early next year (which will bring flash support), so it's a very capable device.
It has no access to the Android Market and B&N plans on developing its own locked down app store (like Apple).
With that in mind, what apps do you want?
First on my list is: