Longhorn not based on .NET
by Nikola Strahija on May 27th, 2005 Although Microsoft intended for Longhorn to be entirely based on .NET 2.0 it seems only some parts of the upcoming MS operating system are going to be produced in this manner.
Many experts believe that MS developers rather gain compatibility at the expense of the superior developer environment of .NET
But the casualty looks like being the ground-up Managed Code architecture, which forbids one process from hijacking another, presenting a key weapon in the war against viruses.
Managed Code API project seems to be offshored somewhere closer to Siberia, and more modest lock-downs, such as No Execute pages being promoted as a good-enough answer.
This is not an unknown practice for MS. Last summer Microsoft detached WinFS search and storage technology from Longhorn and out into a service pack, for companies reluctant to upgrade that the Avalon UI libraries would be available on XP.