Have you try Ubuntu 11.04 Natty yet? I think mostly all of us will try it on virtual machine first. Yes, in fact i try install it on my virtualbox. But after the installation, i keep getting error saying my virtual machine does not support 3D for unity to work. So, how do you solve this?
Steps to take
1# Ok the first thing you need is to install Virtualbox or if you had Virtualbox, just open it up.
2# Now you need to create new virtual machine after that go to settings and click on display check “Enable 3D Acceleration” option.
3# Download ubuntu 11.04 latest and install ubuntu 11.04
4# After the ubuntu 11.04 installation (you will see the error regarding no 3d display, just ignore it), now you need to install Virtualbox guest additions for this you need to click on Devices–>Install Guest Additions
(this start a VBoxLinuxAdditions.run script so you need to run this script when it is done close the terminal and restart yourubuntu 11.04 virtual machine)
5# Now your unity should be working under virtualbox.