The fact that Motorola has sold its stake in Symbian has been seen by some as a sign that the market for operating systems is about to "mature" in the phone business.

There's a more specific reason for Motorola's position: The company wants to sell mobile cell phones to the Chinese market. China's rulers have made it entirely clear that they want Linux, that they definitely don't want Microsoft, and that they can't really see the point of Symbian. And (these leaders might wonder) why is Motorola a 19 percent shareholder in a software company, anyway? Is it because Motorola executives are in some way skeptical about Linux?

In those circumstances, I'd sell my Symbian stock, too. China is looking like a bigger and bigger market for mobile devices, and (even more to the point, perhaps) the source of most device manufacturing for the next decade. And of course, it isn't even slightly skeptical about Linux.

Neither is Motorola.