The Loop has posted a first look of OS X Mavericks—with NDAs covering developer access to the OS, this is one of the first hands-on reviews by a trusted Mac source (Jim Dalyrmple) we've seen. He looks at iCloud Keychain, Notifications, Calendar, the new Finder, Finder Tags, Maps, and discusses the design choices Apple is showing with the new desktop OS (Calendar is showin in the image below). He also discusses the value of Apple's efforts at integrating information and technology. It's a very good read that has us even more excited about Mavericks.
Check It Out: The Loop Posts a First Look for OS X Mavericks