I was pleased to read that NASA recently redeveloped their website using WordPress. This article gives insight into why it was a good choice for the government agency, with the breadth of resources due to widespread WordPress use and popularity being a major factor.
I wrote a post a few years ago to support that use of WordPress and open source benefits the small businesses that specialize in this platform. Numerous large corporations have built development platforms that are also easy to use, but once on that platform, you are helping corporations gain more power and revenue at the “expense” of the little guy. Moving from a proprietary platform generally involves redevelopment. Moving from one WordPress.org platform to another may require some technical attention but can also be seamless.