Clicking x on note should hide notes not delete them!!! Add a delete in the pop up.
Love the interface but immeditely made the mistake of clicking a note x box thinking it would hide it, it doesn't it deletes it completely for all users.
Either remove the x, or make it activate 'hide notes'
Another idea is never delete notes, have a kind of grid view in the back end to see all the notes. There is a danger that one client might delete notes from another contributor and we would never know!