Plus 1
Facebook had been a quasi universe unto itself until it plastered its "Like" button all over the Web last year. That's a big potential threat to Google, which makes billions of dollars serving as the hub of the Web.

Web users already spend more time on Facebook than Google, and Facebook recently passed Google as the most-visited website on the Internet. Worried that people will increasingly rely on their Facebook friends to tell them where to go online rather than Google, the search engine tried its hand at the referral button game when it launched "Plus 1" in March.

By clicking the Plus 1 button, Google users can recommend links to their list of Google contacts when they search for related topics. Currently, the feature only appears in Google's search results, but it will soon make its way to third-party websites just like Facebook's Like button.

It's too early to tell whether Plus 1 will be a success, but Google said users have begun to report some advantages over Facebook's button.

"Plus 1 tells people you like something without spamming your friends," said Fred Vallaeys, product evangelist for Google's AdWords.

Last updated May 23 2011: 5:38 AM ET
Join the Conversation

Euros, private investments, telecoms as utility companies, and of course, Fukushima. 2011 has brought sweeping change to the world of green More

The media has called every breaking news event since Twitter's launch the service's coming of age. Here's the proof that Twitter is all grown up. More