If we want a truly open and transparent government, all it's to relay on open standards and open source software.
The reliance on proprietary software, and closed standards, would mean that the government would be at the mercy of a particular vendor or whoever hold the rights to the patents to the the standard. This is unacceptable, since the government shouldn't have to be subject to such limitations.
What's more, every we all have the right to study the software that the government uses to see how it works and to make sure that it does what the government says it does. After all, we all have to interact with it, and need to be certain that it does what it made for in the best way possible.
On the open standards, one of the main reasons to use them is the fact that all should be able to access the government's platforms without any limitation artificially imposed by a third party. By using open standards, government could make sure that all the people have equal and fair access to its platforms.
Most importantly, the government should be laying the frameworks for open standards, and creating an environment in which open source to become the norm. In our digital world, open source software and open standards need to be the foundation to make sure that we all have access to it in a level playing field.
After all, the government has to represent the interest of the people.