Phoronix has lots of interesting stuff on their site; but before you go through their site in general, check out their benchmark test comparisons between Apple's new Snow Leopard OS, Ubuntu 9.04, and Ubuntu 9.10(alpha)

http://www.phoronix.com/scan.php?page=article&item=ubuntu_karmic_leopard...

And this is their benchmark for Java performance between Vista and Ubuntu

http://www.phoronix.com/scan.php?page=article&item=java_vm_performance&n...

And this is a link to a direct benchmark comparison between Ubuntu 9.04 and Vista!

http://www.DOH!-NoSuchComparisonExists.com

There is no such comparison! Because it is illegal for anyone to do a comparison between XP or Vista and any other OS and publish the results! Isn't that great? Anyone using windows XP or Vista is bound by the End User Licensing Agreement that specifically prohibits anyone from publishing the results of any benchmarking without expressed prior consent from Microsoft. Do you think they would allow an article showing specific and reproducible results that was not fully flattering to their system? If you do, I think I may have a bridge to sell you...or maybe some ocean-front beach property in Kansas.