Mac OS X versions (builds) included with Intel-based Macs
It is often confusing to try and figure not only which minimum version
of OS X supports a particular Mac, but what specific BUILD of that OS
version.
Here is the Apple Kbase article that clears it all up:
http://support.apple.com/kb/HT1159?viewlocale=en_US
Quoted from email from Tim Parker, Sr. Systems Engineer, Higher Education Division, Apple to http://lists.stat.ucla.edu/mailman/listinfo/osxforum