Its 350cd/m2 (brighter than the wonderful Samsung Q1 Ultra / Kohjinsha 1024×600 screen) and has a contrast of 400:1. PPI is 227 which is fairly high (same an N800, slightly more than the U1010 but less than a Sony UX) but in a handheld device, it could work very nicely.
Looking at the specs, the panel takes 200mw with the backlight taking another 800mw near full brightness. That’s not groundbreaking but acceptable I guess.
If you’re interested in more info, your keyboard is: NL8048HL11-01B. There’s a copy of the press release at Akihabara.