Groklaw figures that that software patents are going away. Not dead yet, but soon. See Bilski - What It Means.
The courts are getting conservative on the definition of "patent," returning to its original definition that involved mechanical devices. A recent court ruling made it clear that patents should be "tied to a particular machine" and involve "transformation."
As Microsoft wrote in a friend-of-the-court brief, "We don't make machines." And so all of its patents are one more court ruling away from being unuseful, given the trend in rulings.
As a former CEO of SolidWorks once told me, Our software patents are our defensive warchest. And now that warchest (accumulated at great cost in patent lawyer and processing fees) may be approaching a value of worthlessness:
In a lawyer's careful way, I believe he is indicating that Microsoft, and any other software vendor holding process patents, will think twice now before trying to throw such patents around in a courtroom.