Except you can argue that we don't have only one twitter. We have many, and potentially thousands. I can fire up my own version of twitter in a couple of minute

Except you can argue that we don't have only one twitter. We have many, and potentially thousands. I can fire up my own version of twitter in a couple of minutes. I (or my group, clan, subculture, whatever) can fire up my/our own facebook in minutes. OTOH I only have one electric power supplier to my home.