The article is pretty shallow in the sense that it just casually glosses over a few key characteristics that make the server/datacenter space an interesting battlefield for the current round of architecture wars.

It will be an interesting next couple of years. Intel didn't sit on their hands with this one, like they did with the mobile market. They saw the potential for ARM SoCs, using a large number of smaller/lighter cores to take market share in things like simple web servers or hosting static data. Their response was their Atom based "Centerton" which is cannibalizing their own Xeon line.

As for more CPU performance intensive tasks, ARM has yet to prove itself in the performance/watt arena, especially in the 64-bit realm of server features, like error correcting code or RAS. Most sys admins building infrastructure like to play things safe, since they have to live with their decisions for years.

It seems like ARMs biggest advantage will be price, and the SoC business model of custom tailoring silicon for a customer's needs.