In case you missed it yesterday, Apple announced that it will be launching its OS X Mountain Lion operating system this July for just $19.99. OS X Mountain Lion will be available from the Mac App Store for existing Snow Leopard and Lion users.
Anyone that purchases a new Mac from June 11, 2012 until the launch of the operating system is eligible for a free upgrade within 30 days through the Up-to-Date Program.
OS X Mountain Lion has over 200 new features for Mac, including Messages, Notification Center and Facebook integration in the Fall. A developer preview is currently available from the Developer Center for registered Apple developers.