Good -and valid - points. I was really hooked on getting a Nook too and the fianly decision was the fact of availability (getting a pig-in-a-poke) and the touch screen keyboard. My fat fingers just have no luck at all with non-keyed keyboards. And annotation is a MUST have for me.
The Kindle DX's screen size put me over the top. For normal reading the 5 or 6 inch screens are more than adequate but for studying and intense reading being able to glance back up a large portion of the page was hat I wanted.
Good luck - I hope you have a good experience with the nook.