WindowsNT is remarkably well suited to porting to other arch. This was done on purpose to hedge against x86. Dead one day, reactivated the other. MS needed to brake the 4Gb barrier and they would have done anything to get consumer priced 64bit chips.
Itanium was a dog. We had an Itanium SGI "supercomputer". Everything about it that SGI designed was amazing (hot swapping cpus). The cpu was a dog.