The "Itanic," as many have joked about Itanium, may be ready to slip beneath the waves. Microsoft has announced that it will no longer develop new software for Itanium. Server 2008 R2, SQL Server 2008, and Visual Studio 2010 are the final versions Microsoft will release. They will support the three until 2018, however.
Granted, the vast majority of Itanium customers are buying mission-critical systems from HP, like the NonStop and Superdome servers, and run HP's HP-UX flavor of Unix. Still, losing Microsoft is another blow to a processor that never had major support.
More than 20 RAS features first found in the Itanium are now in the Xeon 7500, and while Intel has not said it plans to phase out the Itanium in favor of the 7500, the writing is on the wall.
It should be noted that mission-critical servers are not quickly replaced. Some mainframes have been on the job for more than 20 years. Itanium will remain in the marketplace for a long time, and the Xeon 7500, even with all the hardware and software support, will take equally long to work its way into the marketplace. What the Xeon 7500 shows is Intel has managed to take the same architecture that once made up our old 386 PCs 20 years ago and turned it into a server processor that runs without ever crashing or needing a reboot.