Can you let me know what page you're testing on, as that will help us diagnose where the problem is coming from.
By adding those tags, you're adding a lot of social widgets from the different networks. Those load directly from those networks and should load very fast. However, there are many browser add-ons, firewalls and other things that could interfere with the loading process. We'd need to see the slow page in action to determine where the problem is.
Also, if you haven't already, test from different computers and browsers to make sure it's not a specific computer that is having the issue.
Thanks,
Alex