They installed WordPress into their website, and then customized it to look
like the rest of their site. So essentially, they made their own theme.
In fact this is what they call their theme:
You can install WP for free and do the same thing.
It involves install, configuration, and customizing XHTML, CSS, PHP, etc.
What they did was the best way to do it (in my opinion). They have their own
WP system on their own webhost server (no remote blog services are used).
This gives them 100% control over the content, theme, files, MySQL, etc.