If I had name the biggest difference between the attitudes at Microsoft vs Apple as to how they build their operating systems, it’s that one of Microsoft’s primary concerns is backwards compatibility, whereas Apple isn’t afraid to jump off the cliff to a better place, knowing it can’t go back.
A lot of what is going on underneath the hood of Windows involves shims, workarounds, and downright kludges to allow old apps and a gazillion third-party devices to work. From a puristâ€™s point of view, itâ€™s got to be ugly. — Ed Bott
You wouldn’t see Microsoft making a jump across processor lines like Apple did to Intel, saying a (prolonged but firm) bye-bye to anybody who bought a Mac before this year. Microsoft would get crucified for such behaviour.
But now that Microsoft has mature, stable (and free) virtualisation technology, maybe they can make a leap. What’s to stop them totally re-engineering Windows to remove all the messy stuff (some of which dates right back to the early versions of DOS) and telling anybody who wants to run an old application that they’ll have to do so on a virtual machine?
(From an idea out of a discussion with Matt.)