Mountain Lion is $19.99.  The software update brings a handful of iOS features to Macs, including the notes and reminders apps. It adds a few other things, like Twitter integration, Apple's Game Center, and iMessage services. There's also a new security feature called Gatekeeper, designed to fend off malware by controlling what applications can and cannot be installed. However, users should be aware this may not offer full protection against malware and viruses and should consider installing other antivirus and malware protection.

Required Specs:

  • OS X v10.6.8 or later
  • 2GB of memory
  • 8GB of available space
  • Some features require an Apple ID; terms apply.
  • Some features require a compatible Internet service provider; fees may apply.

Supported Macs:

  • iMac (Mid 2007 or newer)
  • MacBook (Late 2008 Aluminum, or Early 2009 or newer)
  • MacBook Pro (Mid/Late 2007 or newer)
  • Xserve (Early 2009)
  • MacBook Air (Late 2008 or newer)
  • Mac mini (Early 2009 or newer)
  • Mac Pro (Early 2008 or newer)

Mountain Lion is available for purchase on that Mac App store for $19.99.  If you have recently purchased a new Mac between June 11 2012 and July 25 2012 or after July 26 that did not include Mountain Lion, you may qualify for a free upgrade to Mountain Lion.  For complete information check out Apple's Mountain Lion Up-to-Date site.