Today, Google launched +1, a button that users can click on blue links in Google Search results to say, in Google marketing's words, "this is something you should check out."
Beginning today, a small percentage of Google search users on Google.com in the United States searching in English will now see a +1 button next to search listings, when they are logged in. An example of this is shown in the video above.
Google will use all the recommendations to not only improve search results, but also to bring content and URLs into some sort of content stream on Google.com that will look a lot like the Twitter stream and the Facebook News Feed looks now.