This needs to be done, for one, so we can figure out just WHAT the role of something like Twitter really is in this recent change of power in Egypt.
I'd argue that when the government killed cell-phone service and internet (cell above all), that alone was a major impetus to enrage people. Everything else that runs on those basic portable devices doesn't seem to change the game much... cell-phones and portable computing are the core of it.
One thing I've noticed is that humans aren't built for the amount of typing, keying, txting, gaming, and other repetitive activities that we're doing now, and starting young. There are kids with AC joint issues, and teens with radiating numbness in their hands. I feel that Twitter, FB, Forums, Skype, etc... these are all different facets of the total package that needs to emerge.
As speech recognition is unlikely to become viable as a primary means of input in this decade, gestural interfaces and the possibility of haptic feedback to reduce impact seems key. (no pun). Everything indicates that when you make these means of communication tied to cellular and other communications networks more accessible, people flock to it.
So... you join people of disparate backgrounds, ages, sexual preference, gender, intelligence, education, race, religion, etc... and if they want to and are able to, they can hide it all. On the other hand, you can share ALL of that in an instant on a profile for the public or 'friends' to consume. That is one hell of a binary situation that people are yet to take responsibility for. Yes, privacy is a great thing, but people have to realize that privacy is literally the currency of this new form of communication.
