Good, but if you really want fast performance, I'd suggest that you further cache those numbers in a local database and hardcode them into the page. If using Jekyll (or your favorite static site generator), you can have it go pull up-to-date numbers when you generate the site.
I've done this on some of my sites and it's wonderfully efficient. Most users don't care what the current count is and you can reduce page load times by dropping additional DNS lookup and removing the iframes from DOM rendering. You may not realize it, but these social buttons take a lot of cycles on page rendering engines so it's an easy win to reduce overall page load time. Assuming you can convince marketing. :)
I've done this on some of my sites and it's wonderfully efficient. Most users don't care what the current count is and you can reduce page load times by dropping additional DNS lookup and removing the iframes from DOM rendering. You may not realize it, but these social buttons take a lot of cycles on page rendering engines so it's an easy win to reduce overall page load time. Assuming you can convince marketing. :)