After the second beta version of iOS 7, Apple released to developers OS X 10.9 Mavericks Developer Preview 2. The second preliminary version of “desktop” operating system code received 13A497d, which is considerably different from the first build OS X 10.9 DP1, which had code 13A476u.
Changes in the new version of the system is not too much, but they are still there. Improved overall performance, Safari received minor interface changes, changed the button to send the message in the Notification Center, improved iCloud Keychain, became functional Migration Assistant, improved performance when previewing files.
Registered developers can download the OS X 10.9 Mavericks DP 2 in a special section of the Apple website or from the Mac App Store.