Now that the production release of Ubuntu 10.04 Lucid Lynx is out, users should consider upgrading. Luckily, Ubuntu/Debian (unlike some other distros) makes it really easy to perform an upgrade without breaking things or retaining extra clutter from the pervious version.
I am running Ubuntu 9.04 Karmic Koala in a VirtualBox instance on my Macbook Pro. The first set of commands can be used universally for all users running Ubuntu on any platform and the second are specifically for upgrading the VBox tools to work with the new kernel.
Upgrading Ubuntu (steps for all users):
apt-get clean apt-get autoremove nano -w /etc/apt/sources.lst
(change all references of “karmic” to “lucid”)
apt-get update apt-get dist-upgrade reboot apt-get autoremove
Upgrading VBox Tools (for VirtualBox users only):
cd /cdrom ./autorun.sh reboot
Once you log back in, verify that window resizing and mouse traversal in and out of the VM work correctly. If so, you should be all set and your upgrade is now complete. If you run into any issues, feel free to email me and I’ll do my best to give you a hand.