The 7-Zip compression results are not terribly interesting. Xcode4 with the Clang puts it right in line with the Linux performance while the older GCC 4.2.1-produced binary does not perform as well.
When looking at the Gzip compression performance, the Mac OS X HFS+ file-system is still faster than EXT4. It would be interesting to see how Btrfs performs in relation to Apple's mature file-system, but that will be saved for a future article on Phoronix.
The Ubuntu 11.10 stock configuration had a slight advantage over Mac OS X 10.7.2 when it came to the Fhourstones performance.
Ubuntu 11.10 was also doing much better with the Himeno Poisson pressure solver performance.