In a recent thread at WebmasterWorld, some members have reported that Google is asking searchers to suggest some URLs for specific searches. "Help improve search for everyone" is how Google is asking for suggestions. Google asks the users to

Click a link to submit a link. The link open a form where you need to login.

Google explains: “If you click yes, we'll save this suggestion with your Google Account so we can use it to improve your search results. This is an experimental feature and, based on this experiment, we may come up with other improvements in the future. Like all data in your Account, your suggestions are subject to our Privacy Policy. If you want to delete one of the suggestions from your account, just repeat your search and click "withdraw" next to the saved result.”

After the submission of the new URL is done, it takes you to a 404 page that is at http://www.google.com/reviews/w/nominate.

Forum discussion continues at WebmasterWorld.