Q: cant sync my notes with iCloud

I am experiecing the same problem. In addition, when I re-add my iCloud account to my Mac (I had to erase my hard drive), I have to configure my iCloud email account manually inside the Mail app. It used to automatically configure itself. Not sure if this is related.

Same for me.. after disk cleanup everething is fine, just the Notes sync to iCloud is not activating.. from iPad/iPhone  it "just works"

The Apple Services System Status page has been updated to show that Apple is aware of the problem with iCloud Mail and Notes, so hopefully we should have a fix soon.

http://www.apple.com/support/systemstatus/

It looks like the issue has been resolved. I deleted my iCloud account from my Mac and re-added it. The configuration, including Mail and Notes, went through with no problem.

For the one who have a similar problem, following the instruction into this article could help (reseting iCloud documents without deleting them).