Well, the full-touch capability is a big part of it. On the nook reading an article amounts to:
Tap to wake up the screen.
Tap again when you realize the screen wasn't woken up.
Tap the up/down arrows a few times, wait, tap some more, hit enter.
Read, hit back, repeat previous step.
Move onto next section.
Or just simply use the TOC, but then you lose the nice formatting of the article descriptions.