I have been getting a few questions about the +1 button people are seeing in the Google search results, both in the ads sections and the organic sections.  Here is a letter from Google that explains it in good detail for the adwords clients.

If you would like us to add the +1 button to your site, just give us a call.

If you have been maintaining your own plugins then you can install the +1 button with a plugin on your site, Google +1.  However, before installing another plugin check to see if your current Social Sharing plugin such as SexyBookmarks has the Google + included.

The Google+1 button is similar to the Facebook Like button, it is part of Google’s efforts to advance in the Social sharing environment.  You can read more on it on Google’s page at +1 Button.

Dear Subscriber;

In the coming weeks, your search results and ads on Google will include a +1 button, which users can click to recommend your ads. You don’t need to make any changes to your account in order to take advantage of them. The final landing page URL of your ads can also appear on the Google profile of any user who +1’s your ad.

Here’s how the +1 button works:
Let’s say you own a hotel in Madrid. Brian had a lovely stay at your hotel last summer. When Brian starts researching accommodations for his next trip to Spain, he searches on Google while signed into his Google account, and sees your ad. He clicks the +1 button on the ad to recommend it to his contacts.

When Brian’s friend Ann plans her trip to Spain, she signs in to her Google account, searches, and also sees your ad – plus the personalized annotation that Brian +1’d it. Knowing that Brian recommends your hotel helps Ann decide where to stay during her travels.

Think of the +1 button as a way for fans of your business to recommend what you offer, for all their friends and contacts to see. By helping searchers see more personal, relevant ads, we believe you’ll see more qualified traffic. You can also add the +1 button to your site to give your customers the opportunity to +1 your site after visiting it.

The Google AdWords Team