Facebook/Twitter/Google+/はてぶのSNSボタン高速化(async)

基本的にasyncを入れていくだけです。

はてな
async="async"

<script type="text/javascript" src="http://cdn-ak.b.st-hatena.com/js/bookmark_button.js" charset="utf-8" async="async"></script>

twitter
js.async = true;

!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.async = true;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');

Google+
po.async = true;

(function() {
  var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true;
  po.src = 'https://apis.google.com/js/plusone.js';
  var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s);
})();

Facebook
js.async = true;

(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id; js.async = true;
js.src = "//connect.facebook.net/en_US/all.js#xfbml=1&appId=247875698724916";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));

いまだと各サイトで非同期読み込みの方法が書いてあります。