Apple OS X Mountain Lion is now available for upgrade, there could be three major possible scenarios for an upgrade and here are they :
- Your Mac was bought on or after June 11, 2012 - You will get the "Mountain Lion" upgrade for free, simply claim your free download coupon and download from Mac App Store.
- You have OS X Snow Leopard/Lion installed and you bought your computer in late 2009 or after - upgrade for $20 through the Mac App Store.
- Older computer - Check system requirements and upgrade to Snow Leopard or Lion and then procces to "Mountain Lion" upgrade.
Here are screenshots of OS X Lion to OS X Mountain Lion upgrade process.