I read an interesting report this week in ZDNet UK that supports my longstanding position that cost is only part of a government's decision to move to open source. Many reasons for the adoption of open source software within certain countries relate to cultural and political factors. Of course, cost is one consideration; however, it is not the only consideration, and it may not be the most important one.
Because developers have access to the source code, open source software becomes a good method for building a local software ecosystem and can provide a boost to the local economy. As governments and companies begin to use open source software, local software development and support companies begin to form. These local companies can support the open source software, provide consulting services, localize the software into additional languages, and perform other development tasks. This boosts the economy by providing a mechanism for governments and companies to build a local software ecosystem where they pay local companies to do work that would normally have been completed by a large software company like Microsoft or IBM.
This also ties into an anti-American sentiment held by some countries and governments. Some people believe that the United States is already too powerful. By continuing to fund American software and consulting services, some countries are concerned that the United States could become even more powerful. Many governments would like to reduce their dependence on American software to become more independent and self-sufficient as a nation. Open source software (in addition to other local, proprietary software) is one tool that some governments use to address this issue.
I do not necessarily agree with the ZDNet suggestion that open source may be "too close to socialism" for the United States. I suspect that adoption by governments in the United States has lagged due to misperceptions about the security of open source software and other reasons. On the other hand, governments in China, Europe, Brazil, and others are encouraging the use of open source software. Their reasons are varied; however, culture plays a strong role in the desire to use open source. The cultures of some countries (China, India, and Brazil) may simply be more compatible with the open source community mindset. If you are interested in this topic, I recommend reading Open Sources 2.0 edited by Chris DiBona, Danese Cooper, and Mark Stone; it has several chapters on open source usage within particular geographic locations.