I can see this page getting pulled pretty fast depending what kind of mood Apple is in. 😉
But in essence, all it really is, is the current xServe picture and setup with the G5 specs taken form the PowerMac page off Apple.com. I'm sure someone could mock this up pretty fast, as obviously was the case here!
Regardless though, I am pretty sure we will be seeing G5 xServes at MWSF, or shortly thereafter - they are definitely due for updates!