Canonical has released its newest Ubuntu. This is the Ubuntu 11.04 Natty Narwhal for netbooks which is a daily build for testing purposes according to netbooksreviews.net.
It uses Unity as the default interface same as Ubuntu 10.10 Maverick Meerkat. But you can still use your preferred desktop environment if you are not comfortable with Unity. To download the latest build you can go here then choose from the list. The ISO is more than 700MB so you need to burn it to a DVD or use a USB drive and it needs a minimum of 256MB RAM for the installation.
This is in its alpha stage so expect some bugs when you use it. If you do encounter bugs then you can file them in Launchpad. You can also go to Ubuntu Forums for Natty Narwhal testing. There you can seek help in case you encounter problems and exchange notes on those running Natty on their systems.
Ubuntu 11.04 ISO downloads : http://releases.ubuntu.com/natty/
Ubuntu 11.04 ISO torrent downloads : http://www.ubuntu.com/download/ubuntu/alternative-download