The letter

Some more clues..
http://news.bbc.co.uk/2/hi/middle_east/4752831.stm

Quite as expected the contents of it, I'm pretty suggestive the US will hide part of the contents of the letter before releasing it to the public, but that of course is an inconspiriacy theory.

The various aspects of 911 being kept secret by US are something that will catch the future media coverage, I think US will try to explain that as the Bin Laden's anger to US when the US deployed half a million US solders to Saudi, while their group was paying by US at that time before their arrival to defended the Soviet, the US took all the credits for it, and shadowed down Bin's group achievements.

http://news.bbc.co.uk/1/hi/world/south_asia/1551100.stm

Speaking of whether there is any other aspect of 911 being kept secret, guess we will have to wait of the Time to reveal themselves.