Daring Fireball‘s John Gruber on the B&N Nook Color:
Just watched the demo video in this post (Flash required, alas). The Nook Color is so painfully slow it makes me embarrassed for Barnes and Noble. Horrendous scrolling and zooming and touch responsiveness. Just horrendous.
The video in question can be viewed at CrunchGear. I agree with Gruber: the UI is extremely laggy.