These are the settings for an @icloud.com address. I thought that these have been only rolled out to developers with ios6 beta.
Please make sure that you have setup your email address correctly under accounts to firstname.lastname@example.org and that you are also only viewing the access privileges for this account.
MacOS 10.8.2. I turned iCloud sync off and then was not be able to enable Mail/Notes sync.
So, the Mail iCloud sync I fixed by creating iCloud accoun in the mail application (as described in that post). But Notes was offline any way.
My fix for Notes is the following - use another Mountin Lion mac to create yourself as user there, go to iCloud preferences and enable all apps sync. Then go to yours mac iCloud preferences and enable Notes sync. In my case it works.
I hope to help somebody, good luck.