This site may harm your computer - Google error!

If you used Google search during the last few hours, you might have noticed that all websites have a "Warning - visiting this web site may harm your computer!" message. It seems to have been sorted now. It's not that big of a problem at all, but it draws attention to the fact of how much internet users rely on Google. I have already seen messages related to this on several online forums that I visit, and more is sure to follow, including people worrying about lower amounts of traffic and sales today. Google is, undoubtedly, the leader among search engines, and a lot of people can't imagine browsing the net without it. I myself do tens of searches a day, if not more. I like Google myself, but then again, monopoly is never a good thing.

(Edited) and here's an official explanation from the Google Blog:
http://googleblog.blogspot.com/2009/01/this-site-may-harm-your-computer-on.html