> Update: As we suggested might happen in our Lion review, Mountain Lion's developer preview appears to do away with support for any Mac that cannot boot into OS X's 64-bit kernel. I'll link you to that page of our Lion review again if you'd like deep technical information about what that means, but the short version is that a wide range of Apple's products from 2007 and 2008 are being dropped regardless of whether they include a Core 2 Duo processor. The list of supported Macs includes:
• iMac (mid 2007 or later)