I have some wishes now, after I have been using Ubuntu One for a few months:
1. The bandwidth bug to be fixed
2. Have a progress bar or indicator
3. A way of making Ubuntu One forget a username and password it is using/keeping
4. A log. It can be a window showing what is being done and what has been done. When U1 is working, the same window may show the progress for some files. A simple text based log is usefull - let it exist, anyway.
5. A way to sync certain files before others (especially helpfull, so big files does not stay in the way of sync small but very important files)
6. A way to disable the popup tips. (and I prefer logs, so I never miss anything happening when I am away).