The Nook Glow is virtually identical to "The All New Nook Simple Touch", so I'm going to skip most of the details about the reading features and focus solely on the screen.
Like you've probably read elsewhere, the Nook Glow has a light in front of the screen, not behind. The light is emitted from a layer laying on top of the screen. This is an important detail because at least one of the launch day reviews said that the Nook Glow had a noticeably degraded screen quality.
I disagree. I have a Nook Touch, Nook Glow, and a Kindle Touch on my desk. I cannot see any real difference between the 3. The gray bezel around the screen on the KT has a bigger effect on the screen qualities. And that is coming from someone who is exceptionally picky. I can find fault in perfection (it's too perfect).
The Nook Glow has a slider so you can adjust the amount of light its putting out. This is good because I found that I could read comfortably with the light set to the dimmest setting. The highest setting is as bright as shown in the commercial. You can use the Nook Glow as a flashlight if you like. In fact, the screen is bright enough that you could probably use it to signal with Morse code at night.
One of the launch day reviews said that the Nook Glow had a gray bar across the top where it wasn't lighted as well as the rest of the screen. They also said that the light was uneven, with some lines of text looking brighter than others. I can confirm the gray bar, but it's not an issue. It's usually up above the text on the page.
But I'm not so sure about the unevenness of the light. Yes, you can see it in the photo, but I'm not sure that it will bother you all that much while using the Nook Glow to read.
You'll have to decide that for yourself.
One reason I got the Nook Glow was that I was looking forward to hacking it and turning it into an E-ink tablet. I know a number of people who love their Nook Touch, and I though the addition of a light would only add value.
Nope. The problems with the lighting might not bother you while reading but they could be serious issue when the Nook Glow is used as a tablet. I think I would be more likely to be bothered while playing a game or browsing the web.
But that's just my opinion. What's yours?