[citation][nom]thearm[/nom]They should do what Apple did and build a whole new OS using Free BSD. IMO anyway.[/citation]
If they used Free BSD, then it wasn't "whole new".
Also, dont forget that a lot of financial and manufacturing businesses still have DOS systems that have never been updated, if MS ripped up all compatability for DOS it would have a crippling effect on them. Eventually the world will move to 64 bit and DOS will be a distant memory but even though innovation in the IT world happens on a day-by-day basis, the real-world uptake can be stretched over decades. MS knows this and is pretty good at playing the long-game.