I've never had an HTC-powered Android, so I don't know much about Sense UI myself. I know I've tried a few ROMs that were set up to lool like it for my Optimus, and I wasn't really happy with it. I'm running a ported version of CM7 on the phone right now, and it's nice, but buggy, and plan on going back to stock on it and just waiting for LG to get around to releasing their update.
Regardless, my NC keeps blowing my mind. It may lack a novelty or two, but it truly is a tablet computer. It boots external media even! Kicks ass IMO. I agree with what's already been said; with a bootable CWR SD card this thing's really un-brickable unless the hardware is damaged. And thanks to the developers who are just as in love with this magical gadget as we are, there's more and more features being introduced to Nook almost on a daily basis.
(Thank you Cyanogenmod!)
I cycle everywhere, I haven't been driving since August. It's nice to experience truly mobile computing for a change, instead of lugging around my ancient 17" laptop with 1.2 hours of battery life. NC's battery easily gets me through the day, even when I stop to use the web and pull out my BT mouse, and sit and browse for a while. It seems the battery will even easily last through two standard full-length films over Netflix.