After installing Mac-OS X Tiger, Ubuntu-eee and Xandros on my Asus EEE-pc 900, I now swiched to Debian Lenny. Installing was easy. Running a normal Gnome now. For the wireless I used these links:
http://www.thinkwiki.org/wiki/Installing_Debian_5.0_(Lenny)_on_a_ThinkPad_X200#Atheros_Chipset
http://wiki.debian.org/NetworkManager
http://wiki.debian.org/WiFi/HowToUse
Everything else worked out of the box ;) Nice and easy installer too! I think this one is a keeper. And I love Debian!