Given that Microsoft's core business is Public Relations, in all senses of the words, and that the corporation has proved that FUD is a much more profitable product than competently written software, there is no incentive for it to improve Windows or anything else it sells.
Moreover, there is little motivation to change: having ground Apple and other upstarts under its heel, The Boys from Redmond need only to pre-pre-pre announce the next "improvement", cash some more options, and laugh themselves to sleep while worshiping an effigy of P.T. Barnum. The only competitors with the political, financial, marketing, and HR muscle to mount a frontal attack are governments, and _they_ already took their cut.
Lacking the authority to mount an inquisition - a prerogative of the governments they just settled with - Microsoft has no way to intimidate or outspend those whom are working for free to create and improve things like GNU, Linux, BSD, and Apache. It remains to be seen if Open Source will continue to fly under the radar, or if Mr. Gates' minions will manage to co-opt or suppress the efforts.
The automobile industry's only "competitors" are alternative modes of transportation such as urban mass transit, and your friendly local oil baron ripped up the tracks long ago: the industry hasn't had, and hasn't needed, any meaningful change in almost a century.
The odds are overwhelming that you drive a gasoline-powered, rubber-tired, human-guided vehicle which is fundamentally the same as a Model T: this popular product is dangerous and expensive to maintain, but automakers are doing just fine while selling add-ons such as seat belts and side-impact airbags.
The fact that you feel the automotive industry has even the appearance of competition is proof prima facie of Madison Avenue's expertise and the impressionability of the average consumer, and with that in mind I'll declare Microsoft's monopoly safe for the moment.
William Warren (Filter noise from my address for direct replies)