@Some Guy: True and I tried to be clear on this in the story. Ivytown and X-Gene are not head-to-head competitors.
However, it's worth noting OEMs say many sevrers no longer need performance as much as lower power. For many jobs a high end Xeon is no longer needed if its just about pushing data through the Ethernet and stroage interfaces. So in this way the two very differently focused products are wrestling over a pie of sometimes overlapping workloads.
ARM is targeting microservers, which isn't Xeon based on Ivytown. ARM is going after the Atom-based C2000 processors.
Ivytown Xeon vs. ARM microserver won't be much of a wrestling match: Semi-Truck vs. Fiat 500. One gets a lot of work done, and the other is very fuel efficient. Those meetings on the highway tend to leave one of them pretty squished. :)