Apparently, Canonical doesn't has the time to deal with this feature
Canonical has decided to remove the "Notes" feature from the Ubuntu One interface, on Tuesday, February 28th.The developers in charge with the Ubuntu One web interface said that the U1 Notes feature is not really working as it should and it would eat up a lot of human resources to elevate its quality to make it work properly.
They simply don't have the time, especially in a year when an LTS version, Ubuntu 12.04, is almost ready to be launched.
"We have looked at the improvements required and the resources needed to raise the overall quality of the notes web interface."
"However, with everything that we have to work on in 2012, plus continuing to improve our core services, we just won’t be able to give it the attention it needs," said the Ubuntu One development team on the official blog announcement.
Canonical is not saying the service will be gone for good. Maybe, some time in the future, when the cloud technology improves, it might be back in a better form.
In the meantime, users will be able to sync notes via Tomboy.