The Open Source Paradigm Shift is a solid essay on why open-source software is a significant long-term trend:

I find it useful to see open source as an expression of three deep, long-term trends: * The commoditization of software * Network-enabled collaboration * Software customizability (software as a service) Long term trends like these “three Cs”, rather than the Free Software Manifesto or The Open Source Definition, should be the lens through which we understand the changes that are being unleashed.

Worthwhile read for anyone seeking to understand the importance of open-source.