I strongly support the open source movement, and I believe that governments should, too. First of all, from a fiscal standpoint, open source software tends to be free or very cheap, so there's an economic incentive. Secondly, in my experience, open source software works just as well as commercially-available software. It's a viable, cheaper alternative.
As with many issues, again I believe that government should stay out of the software business. I believe that when you allow governments to start offering open source software you're asking for more spying and intrusion into ones privacy.
I believe that governments should focus on creating a safe environment, free from terrorist attacks, and focus on creating environments that is conducive to creating jobs.