Windows 7 build 7048 vs. Windows 7 beta 1 vs. Vista vs. XP performance shootout - which is best?

How does the latest leaked build of Windows 7 (7048) compare to the beta 1 (build 7000), Vista SP1 and XP SP3 in terms of performance? According to my Hardware 2.0 inbox, this is a question that you want answered. Let’s see if I can answer it for those of you who are interested!