Google recently introduced the Google +1 button for websites, and Google would like you to add the Google +1 button to your site.
But, at this time, I cannot recommend that you add the Google +1 button–it will severely impact your page load time, which will ultimately hurt your website’s usability. Slow page load times will also impact your website’s search engine optimization. Do not implement the Google +1 button at this time.
What’s the bottom line? Do NOT implement the Google +1 Button, it could add more than 2 seconds to page load time.