First, Jessamyn West spotted a Google experiment and posted a screen shot on Flickr entitled, "Google becoming Digg?" Then, Haochi Chen of Googlified posted an item about the "Google Digg-Style Experiment." So, what's up?
According to Google Experimental Labs, "Google is always experimenting with new features aimed at improving the search experience. This experiment lets you influence your search experience by adding, moving, and removing search results. When you search for the same keywords again, you'll continue to see those changes. If you later want to revert your changes, you can undo any modifications you've made. Note that this is an experimental feature and may be available for only a few weeks."
Check it out for yourself (while you can) at http://www.google.com/experimental/a840e102.html.