I installed an early development release of Ubuntu Netbook Edition 10.10 on my new Lenovo IdeaPad S10-3t. While the interface is rather smooth, and more usable than Windows, I found the Ubuntu One feature slow and wasteful. I don’t use Ubuntu One because of its lack of cross-platform compatibility options, and it takes up a nice chunk of screen real-estate in Nautilus just to remind me that “Ubuntu One [is] disabled.” It also tends to slow down the file manager.
To remove it, I simply issued
sudo apt-get autoremove ubuntuone* python-ubuntuone* --purge
… and it stopped bothering me after I logged out and logged back in. Launchpad has a page on this as well.