I'm worried. Consider what happened to Skype. Consider what happened to LinkedIn. I worry something similar will happen to Github. And I love Github.
At some point Microsoft told me I had to change my password for Skype. The "Reset your password" process failed 6 times in a row. I eventually had to create a new, Microsoft ID, to use Skype. I lost all of my old contacts and had to slowly recreate my address book. This is really one of the worst transitions I can recall.
Meanwhile, I act as adviser to a number of entrepreneurs, and the biggest trend of the last year has been "I want to do _______ for professionals, since LinkedIn isn't doing it." The lost opportunities for LinkedIn are very sad.