Paul Thurrott posted part 2 of his "How Microsoft Can Fix Windows 8" articles series

While there are many ways in which to compare and contrast Apple and Microsoft, one of the more disparate differences is the way in which the two companies handle backwards compatibility. Where Apple is (perhaps overly) aggressive about removing legacy technology deadwood from its products, Microsoft values backwards compatibility above all else, and often leaves out-of-date technology its own products, especially Windows, for far too long.

Microsoft's approach is seen as more customer-centric in the sense that it allows customers to more easily upgrade to new product versions as they appear. But there are downsides to endlessly supporting ancient technologies and security is only the most obvious. Windows is far more complex, bloated, and hard to support as a result of this decision. And it makes it harder for Microsoft to make major strides when improving the OS.

  How Microsoft Can Fix Windows 8, Part 2: Virtualize Compatibility