e! Science News is a revolutionary website where absolutely everything is fully automated by harvesting content from other websites RSS feeds, article tags, reciprocal links, and no doubt many other techniques: http://esciencenews.com/

At the fully automated extreme it's a fairly niche idea (as most organisations will want at least some control over their content), however it could certainly be a powerful framework to use for a single section of a website.

Here's a little more information on how it works: http://esciencenews.com/about