I was able to get a review unit of the Asus Eee PC 900 last week but the review unit I got had Windows XP Home pre-installed. Being an ABM (Anything BUT Microsoft) kinda guy, I immediately decided to reformat it and install linux.
First choice is Xandros Linux, the default Linux distribution specifically made for the Eee PC. Unfortunately, it is not included in the CD that came with the package. It may be because of the Microsoft-Asus deal that prevents users from getting the Windows XP Home version and installing Linux, which I find weird since you get more storage with the Linux version (20GB vs 12GB). I even checked the Asus website and found none! I wonder why it is not available. I would have preferred installing Xandros Linux since it is highly optimized for the hardware already.