No, not all software is open source today… nor do I expect all software to be so anytime soon.  That’s why I have to agree with our corporate vision of a mixed-source world.  To make some folks in the IT world fully embrace open source solutions will require applications to be available.  That’s why articles like this one from CNET which highlights particular open source applications, and programs like Novell’s Market Start (designed to help foster high quality open source applications/solutions) excite me.