Microsoft Embraces Open Source?

For as long as I can remember, the theory that Bill Gates and the original Microsoft team did not exactly "invent" DOS has been thrown back and forth. I have always thought that MS-DOS was a rip-off from UNIX. I also have been convinced that Gates and Microsoft ripped off IBM in the original deal that caused IBM to lose considerable market share. Now, a court has found evidence that some of these theories may be correct; please see the article listed below for more details. It definitely makes me feel even better about supporting GNU/Linux and other Open Source efforts. Now Microsoft wants some of their software classified as Open Source -- a move that, believe me, is not motivated by altruism. What is really behind Microsoft's embrace of the Open Source philosophy? Perhaps a way to circumvent licensing issues? Or maybe a new strategy to sneak into even more areas of software development under the false pretense of the Open Source initiatives? I am sure it will not be long for details to emerge.