Is it possible to share notes over Ubuntu One with a public link like in Google Docs? I found a solution here but it does not work anymore. Is there a solution?
Currently, sharing notes in Ubuntu One is not possible. The link you posted in your question shows that it is an idea under consideration and may or may not be actually implemented.
If you really have to share your notes, then copy the contents of the notes and save it as a .txt file and share it on Ubuntu One.