Even when there was the Pentium4 there have been some models featuring the same core of the Xeon version, but then the whole package and what makes a Xeon better than the desktop version wasn't included.
It still was a desktop product.

I stopped reading at "this high-end unit has four GPU slots (two PCI-E x16 v2 and two PCI-E x4 v1)"

1. GPU = Graphics (or General) Processing Unit, and it's the processor on the graphics card. Last time I checked, you didn't stick a GPU into a PCIe slot, you put a graphics card in the PCIe slot.

2. Saying there are "Four Graphics Card Slots" is completely wrong. PCIe x16 and PCIe x4 are NOT graphics card slots, they are general usage slots that replaced PCI and happen to be used by most modern graphics cards. 

Servers have as many as 10 PCIe slots, none of which are used for graphics cards. They run anything from RAID adapters to Fiber Adapters.

3. Almost no video cards out there use PCIe x4, nearly all of them use PCIe x16, these are useful for less bandwidth intensive devices like gigabit NIC's and wireless cards.

This could have been a great review article if it was written by someone who understands technology beyond being a basic script-kiddie level.