There have been apps on FaceBook for a while that let you do all kind of VoIP tricks, but most of them have been basic "call me" apps. Om Malik reported that 8x8 has launched one too, but took them to task for their impersonal understanding of social media writing:
"I hate the random photo (see graphic) that’s now being displayed on my page, especially when it could easily customize it by picking one of my Facebook profile photos instead. Another bonus would be if one could place the Call Me button on fanpages as well."
While FaceBook is becoming more and more a staple in many people's online diets, given how 8x8 is focusing on the business market it likely would have made more sense to figure out how to build this kind of functionality into LinkedIn. Now that would have made them, very "me different."