"The OS X Mountain Lion Up-to-Date upgrade will be available at no additional charge from the Mac App Store to all customers who purchase a qualifying new Mac s

"The OS X Mountain Lion Up-to-Date upgrade will be available at no additional charge from the Mac App Store to all customers who purchase a qualifying new Mac system from Apple or an Apple Authorized Reseller on or after June 11, 2012." - http://www.apple.com/osx/uptodate/ http://www.apple.com/osx/uptodate/ (I'm sure the site will be live tomorrow to get the free update.)