I have been waiting for a full-scale patent war over open source to take place in the near future. Yet, the war has not broken, other than the issuing of cease-and-desist letters to some open source projects, the war has failed to surface.
I have been reading this very good article by Heather Meeker, who I criticised before for another article on software patents. She makes an interesting point as to why there has not been an open source patent suit yet. While I agree with many of her points, I am not so sure that open source is truly free from patent infringement suits. It is true that litigation is expensive, but with so many ludicrous low-quality software patents out there, it is just a matter of time until some company decides to test the waters and enforce a patent in court against an OSS project.