Semi-Official List of Yosemite-Compatible Macs

[HankAZ]

The developer preview builds of OS X Yosemite suggest that any Mac capable of running OS X Mavericks (10.9) is also capable of running OS X Yosemite (10.10). Accordingly, here?s the list from ArsTechnica?s entry on the matter, the presumption as of now is that these Macs that can run Yosemite Dev Preview 1 will continue to be compatible with the final version, though that may change as the final release nears. We?ll be sure to update if anything does.

• iMac (Mid-2007 or newer)
• MacBook (13-inch Aluminum, Late 2008), (13-inch, Early 2009 or newer)
• MacBook Pro (13-inch, Mid-2009 or newer), (15-inch, Mid / Late 2007 or newer), (17-inch, 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)

You?ll notice the primary hardware requirement is a 64-bit CPU, which is generally an Intel Core 2 Duo or newer processor.

Of course, the list of minimally required hardware is going to be different than what offers ideal performance with all the translucent effects functioning as they intend to without degrading overall system performance, but some of that we won?t know until OS X Yosemite is released in the fall to the public. Generally speaking, the newer the computer the better, and the more resources available the better the performance.

OS X Yosemite System Requirements & Compatible Macs List | OSXDaily

 

[kch50428]

I can confirm an early 2008 15inch MacBook Pro runs Yosemite... seems like Safari takes longer to start up but other than that, seems to be fine. I'm sure they'll make things better.