I investigated running a lightweight operating system on my Netbook to get off Windows XP. I looked at Ubuntu Net Remix and Moblin but consider their simplified interfaces too restrictive.
I will be interested to see how the Google Chrome OS compares when it is available.
In the end I installed Kubuntu 9.10 (Karmic Koala) from a USB drive as a dual boot option. Details on the installation and configuration are available in this article on Greenlivinpedia. Being a wiki, you can edit the article and add more information if you wish too.
My overall impressions are that Kubuntu Karmic Koala 9.10 is polished, easy to use, stable and quite slick. For those thinking of moving from Windows XP or Vista, this is a compelling option.