Starting next month Google will introduce the +1 button and personal recommendations to display ads. The +1 button will begin to appear on AdSense for Content and AdSense for Mobile Content display ad formats, image, animated gif, and Flash. +1s will be one additional signal to help determine an ad's relevance.
By socializing Adsense Google aims to improve ad relevance, make their Plus 1 product more useful and of course up the ante in the showdown with Facebook.
The good thing about this feature is that it's completely optional, if your an Adsense publisher and prefer not to show the +1 buttons on display ads on your pages, you can opt out in your account. Check out the example below.
Do you think this feature will benefit Adsense publishers?