The post says you can adjust the brightness.
You can adjust the brightness by clicking the button again and sliding the dial on a Quick Settings screen. Half brightness should be enough to keep you reading in a dark room. You can also turn the light off here or just hold down the "n" button again.
I have one of these and if you are reading on it in complete darkness then the glowlight is very bright, but you do have full control over the brightness.
They probably had to have it on full brightness to illustrate the light for the photos. Makes me wish I were in the market for an upgrade, because I'd love to have a light on my Nook.
I messed around with one yesterday at the local D&N. It is fully tweakable for brightness settings. The issue I have is this new Nook has an anti-glare layer which is cool for sunlight, but I have read this version has lower contrast on the eInk. I guess there is always Pros/Cons for updated products.