We can all pull the "Mark never walked in our shoes" line, but what he is trying to say is that transparency is inevitable as we march forward into the information age. So we might as well accept our convictions and live with them.
As for the people in Egypt there will always be outlets for anonymous communication. However, it won't be found on some tech blog.
Putting faces behind the comments provoke people to consider their opinions more carefully, just like we do in real life. And if you are one of those people who want to lash out, but don't have the guts to do it in face then you should just tell your best friend or keep it to yourself.
Just my thoughts.