i'm using this little bit of code to add a 'pin it' button to my wordpress site. I added in target= "_blank" and it still opens in same window.
<a target="_blank" href='javascript:void((function()%7Bvar%20e=document.createElement('script');e.setAttribute('type','text/javascript');e.setAttribute('charset','UTF-8');e.setAttribute('src','//assets.pinterest.com/js/pinmarklet.js?r='+Math.random()*99999999);document.body.appendChild(e)%7D)());'>Pin it</a>