I think the blog was using iframe tags. Like <iframe src="http://URL"></iframe> which embeds the URL in the calling page. I think the iframe tag should be removed from the standard it's very annoying especially when forums allow it to be used. You end up with someone else's complete site sitting where it wasn't intended to be and most people\organisations would hate their sites being used like that, i know i would.
For more info W3Schools.com.