If you've added Google +1 icons to your pages to - as Google puts it - "help your site stand out," you're doing Google a big favor. By helping those of your current site visitors who haven't yet engaged in "plussing" behavior to start doing so, you're helping build Google's position as more than a search engine (i.e., a social media platform).
With Google+ and +1, Google is trying to out-Facebook Facebook, using the power of the SERP and Display Network advertising to convince us (the advertisers) to do the social media user expansion work for them. Amazingly, it will probably work, because Google gives us something back when we give Google the opportunity to offer our site visitors plus functionality. When someone "plusses" a page on our site, both our ads and our organic results will be enhanced for those specific, socially connected searches where our site would be a fit..... Read more.