Those who add their Facebook or Twitter usernames now have automatic links to those sites respectively around their username/avatar/signature for topic posts. Here are the steps:
1. Go to your profile, which is linked under the text "Profile" in the header.
2. Click "Identity" to start making changes.
3. Scroll down until you see "Facebook," "Twitter," and "Website." Follow the instructions there if you want to take advantage of these optional links.
If you have any feedback on this, please reply below.