Dvorak made interesting points, but his logic is flawed: Microsoft doesn't actually need any successful products to survive.
Microsoft not only has a huge bank account, but it is being handed money by all the peripheral industries that (sadly) depend on Microsoft's proprietary technologies. Those companies will simply never risk destroying their huge I.T. investments.
That's true in the short term, but Dvorak's point is that MS has wasted time and money on diversions that it has not executed well to the determent of Windows and Office. You can also see that the cash cows are in danger because people are moving to new environments that are not desktop/laptop based, like iPods and cellphones. I cant imagine life without my laptop, but others seem to be doing a lot with other devices.
Contrast MS with Apple and Google which have move into new areas with style and excellent execution. MS seems downright frumpy.
Microsoft not only has a huge bank account, but it is being handed money by all the peripheral industries that (sadly) depend on Microsoft's proprietary technologies. Those companies will simply never risk destroying their huge I.T. investments.