Recently I have decided to give a try to Ubuntu One. There are two advantages of Ubunto One over Dropbox:
1) It allows you sync any folder on your computer not just a specific folder like Dropbox. So you could have more than one top level folder synced.
2) It also provides music streaming service and streams mp3 files from your synced folders to other ubuntu one clients without downloading whole folders to each client.
I have successfuly setup Ubuntu One on my Ubuntu 11.10 labtop. But for strange reasons it could not sync my ubuntu 11.10 desktop computer. There were lots of errors in ~/.cache/ubuntuone/log/ubuntuone/logs/syncdaemon-exceptions.log file similar to followings:
UnpicklingError: could not find MARK
UnpicklingError: unpickling stack underflow
UnpicklingError: invalid load key, ‘^Q’
UnpicklingError: invalid load key, ‘^C’
ubuntuone-support@canonical.com directed me to following solution..
u1sdtool -q
sudo rm -rf ~/.local/share/ubuntuone
u1sdtool -c
After above steps, ubuntuone started to sync files on my desktop computer.
At anytime you can check status of ubuntuone with following commands.
u1sdtool –status
u1sdtool –waiting
Main disadvantage of ubuntu one compared to Dropbox is stability and sync speed. It is slow and not as mature as Dropbox. You can verify this by checking its own form, a lot of people are complaining.