One thing I've noticed on my Sony Reader Wifi is that some apps, particularly ones with dark color schemes, don't look good on the screen. This hack fixes that issue for the Nook Touch (I really need to try it on the Sony Reader Wifi).
Attention B&N Folks: Do you want to know something that's funny about this? I was at the Nook Tablet launch, and I distinctly recall your boss saying that there was no value in making the Nook Touch be more than an ereader. I'd say that the video above proves him wrong.