Moving notes to iCloud
Notes in Mail will be removed in iOS 6, and iCloud only syncs notes between the notes apps.

So, Mountain Lion is just a few month ahead of iOS 6 so there is a bit of a missing link between the systems.


  You can create for every "mail.app-note" one entry in the notes app
  from iOS and they will be synced to all your devices.


So copy and paste every entry from the Mail-Notes to a new entry in the notes app on iOS, and they appear in Mountain Lion and on your other iOS-Devices.


  Works between iOS 5, 6 and Mountain Lion.