I don't have a Nook yet, so I can only go by what I am reading online, but it looks like Matthew Miller over at ZDNet is pretty happy with the Nook, and the 1.1 update. He discusses the changes (and includes video comparing the Sony PRS-505 to the Nook 1.1). Looking good to me. Hopefully the 1.2 or 1.3 that is out by the time I get a Nook should have improved it further!
Link:
http://blogs.zdnet.com/mobile-gadgeteer/?p=2317