A couple of days ago, I received an invite to start using UbuntuOne. I have been using Dropbox for a while already and am very happy with that. Now being an Ubuntu supporter, I decided to give it a try on my Ubuntu 9.04 machine. The install went fine and signup was flawless and worked as I would expect. A menu item was put under Applications/Internet and when you run that, the signup process start and an UbuntuOne applet is put in the panel.
Yesterday there was a update that came via Update Manager. Applying the update removes the menu item from Applications/Internet and the applet also disappeared from the panel. I ran into bug #395035. There was basically no way to start the UbuntuOne client. I had a look in Synaptic Package Manager and found a new package called ubuntuone-client-gnome
and installed that. It brought back the menu item under Applications/Internet and running that brought back the applet in the panel. My previous signup setting was still intact and it connected with no problem.
You can also install the package with the following command:sudo apt-get install ubuntuone-client-gnome