Red Hat announced at the end of 2009 that Red Hat Enterprise Linux 6 will not support Itanium, and now Microsoft has announced that Windows Server 2008 R2 will be the last version to support Itanium.
This is not good. HP is the largest vendor of Itanium systems – they should be, since Itanium was an HP-Intel joint venture. Intel just introduced the new Tukwila chip in January, and now Windows and Red Hat Enterprise Linux will not be found on the chip.
Most pertinently for HP, this means that Integrity Virtual Machines running Microsoft Windows and Red Hat Enterprise Linux will neither be available nor supported.
SUSE Linux Enterprise Server (SLES) is still available for Itanium, as is HP-UX, and OpenVMS is due soon. Time will tell if this bailout by Red Hat and Microsoft will affect HP’s bottom line; Intel should be relatively unscathed.
UPDATE: Fixed factual error.
UNIX Administratosphere 
If I were HP at this juncture, I would ask the very important question of Red Hat, “How much”, and purchase this opensource OS outright and continue support.
The problem with purchasing a company like Red Hat is that corporate growth through acquisition (perhaps the darling of Wall Street for decades now) is probably not a good thing. Consider that HP now numbers 150,000 employees, compared to Microsoft at 60,000 and Google at 6,000.
Like Tom Peters says, “No one ever became great by becoming larger.” If I was in charge of HP’s Itanium Operating System Support, I think I’d revitalize HP Linux – but I don’t see that happening, as HP has already stated they won’t support Linux on Itanium 9300 chips.