This test doesn't list Slackware, therefore it is not a real test
FTA: "As you can see the scores of most of the Linux distros are fairly close (within 3% of the number one), with one exception: Ubuntu.......Ubuntu 10.04 was at the very bottom (over 10% behind Chakra)"
Can a user realistically perceive a 3% difference? I doubt it highly. 10%? possible depending on what is happening at the moment (video lag, etc).
With the wide variety of distros out there I'm surprised there isn't more of a spread between them.