Google introduced its own 'Like Button'

Google now allows you to "Like" and vote +1 for the specific results of your search and related AdWords ads.
Part of this is the latest Google Labs experiment that discovered the Search Engine Land.

Google +1 button function as Facebook Like button, and the results of that vote will be more pronounced and will affect the future results that will be displayed during the search.

 After you vote for a score, below will show who is out of your network of contacts on Google also voted for him. Interestingly, except for what you will be able to vote search results for AdWords ads that appear next to them, which will certainly affect the quality score for each ad and the cost to the advertiser.

To participate in this experiment include the option listed under the +1 button.