Ubuntu 10.04 LTS (Lucid Lynx) available on Linode
blog.linode.com
blog.linode.com
http://library.linode.com/troubleshooting/upgrade-ubuntu-10....
My best guess is that they have be mucking around with the RC to make sure everything is working properly and did some final checks once it was released and threw it up on the site while the other hosts actually waited until release.