Google Provides Warnings Of Potentially Hazardous Search Results

Philipp Lenssen found a Google Systems post that discovered Google now provides an intermediary page, for some search results, informing you that the result you clicked on may "harm your computer." You can see this intermediary page for yourself by clicking here, it looks like Google is calling it an interstitial page. Why even list the site in the search results if they may be harmful to your computer? Well, the key terms are "may be harmful," so let the user decide. I wonder if these potentially risky pages get some sort of downgrade in rankings?