Apple now makes it official on which can be upgraded
Well, it has been hinted at for some time now, but Apple has finally confirmed that at least a number of newer Mac OS X systems will not be upgradable to Mountain Lion. This news might be unexpected to some, but it follows the pattern we have seen previously.
The good news is that the list of Macs that will not be able to run Mountain Lion is smaller than we expected. In order to upgrade to Mountain Lion, your Mac must fall into one of the following categories:
iMac (Mid 2007 or newer)
MacBook (Late 2008 Aluminum, or Early 2009 or newer)
MacBook Pro (Mid/Late 2007 or newer)
MacBook Air (Late 2008 or newer)
Mac mini (Early 2009 or newer)
Mac Pro (Early 2008 or newer)
Xserve (Early 2009)
The best news is that you can actually see if your Mac is capable of upgrade to Mountain Lion by simply clicking the Apple icon in the upper left and choosing the “About This Mac” option, then selecting “More Info,” and this should tell you everything you need to know.
You will need to be on the latest version of Lion with all updates applied, or Snow Leopard 10.6.8 in order to upgrade. As with Lion, upgrade will be a download via the Mac Apps store. Users without broadband access should go to an Apple Store to get help downloading it. It is still on track for release this July.