message Request method 'POST' not supported. Notification Center was added in the operating system. Messages. Even prerelease builds were far more stable than I've come to expect from OS X betas, leading me to wonder if Apple's new annual schedule is leading to more careful incremental updates (with fewer bugs) rather than great leaps (with more, nastier bugs).". Apple. Power Nap allows flash storage-based Macintoshes (late 2010 MacBook Air and later, or the MacBook Pro with Retina display) to synchronize with iCloud (Reminders, Calendars, Photo Stream, Notes, Mail, and Find My Mac) while sleeping and also allows a Mac to download App Store and OS X updates as well as make periodic Time Machine backups when it is plugged in and sleeping. Dictation Dictation requires a microphone (built in or external). Retrieved February 16, 2014.