Phoronix compares Mac OS X and Ubuntu.

"Upon the release of the first Mac OS X 10.7 "Lion" Developer Preview, we had delivered early benchmarks of this Apple operating system slated for release this summer. Since then, there has been the release of Mac OS X 10.7 Developer Preview 2 (DP2) so we have carried out an updated set of Mac OS X 10.7 performance benchmarks. This also includes a comparative look at the Mac OS X Lion performance against Ubuntu Linux 10.10."



Link: Phoronix