I was at the Apple store yesterday and they had a new 15 inch PB on display as well as an old one (on the opposite side of the store). Anyway, the new screen is NOT any brighter, IMHO. I compared both at the highest setting and, in terms of brightness, they looked identical to my eyes. The new screen does look better in terms of resolution but the fonts are too small in some circumstances and, as always, YMMV...
Also, the new 17 inch PB looked substantially brighter than the new 15 inch PB that was sitting right next to it.
On another note, I am skeptical of Apple's claims that the 15 inch PB can get "up to 5.5 hours" of battery life. I unplugged the new PB (it was showing 100% on the battery meter) and I waited a few minutes to see what the time remaining meter would say and it never got higher than 3:15 with the brightness set to 75%. When I cranked the brightness up to high, the time remaining went down to 2:45. Then I tried the brightness all the way down, without shutting the backlight off completely, and the time remaining went to 3:40 but, at this brightness level, the screen is barely viewable, especially in a well-lit store like the Apple store.
I just don't see how anyone can get 5.5 hours out of it, especially with the battery being essentially the exact same one that was on the previous generation 15 inch PB.
I hope that helps answer some of the questions in this thread...
