In what appears to be saber rattling (onward to world domination), Microsoft claims that free, open source software (FOSS) violates several of its software patents, and is now starting to take these patent violators to task.
Since it cannot afford to take on FOSS head on (via lawsuits), Microsoft is taking another tack: licensing. You know, we-own-the-patent-to-that-but-we-will-not-sue-you-if-you-pay-us$$$$$$$$$.
Of course, FOSS (specially the Free Software Foundation) isn’t going to take thing sitting down. The GPL license has undergone a new revision to counter Microsoft’s moves; it will be in force this July.
Now, all we have to do is to wait for the legal fireworks (read: lawsuits) to begin.