Warning: I am writing from an Amerocentric perspective. When I talk about protest, I am explicitly talking about "protest in the United States."
Nice article.
I have a related pet-topic. Advances in communications have made it very easy for the young to express their rage to large audiences (Occupy, or the example given in this article). I'm worried about this. I think that Facebook / Youtube / etc are inadequate mediums to resolve conflict. I believe the corporate incentives of these companies (Google / Facebook / Twitter) are partially opposed to those seeking intellectual discourse and change.
My favorite example of Facebook's inadequacy is the lack of a "dislike" button. Facebook obviously has no incentive to allow users to "dislike" potential advertisers and make investing in a Facebook presence a risky endeavor (at any moment, you are at risk of being disliked in the event of a scandal / PR disaster).
That being said, I don't even know how much of a problem the issue addressed in the article is.
I'm sure one could argue that the low barrier to entry for protest will cause protest to be so amorphous to as be useless - but I actually don't even know what the value of protest is!

I wasn't alive during the 60s, and in my lifetime (I'm in my mid to late 20s), I have never witnessed anything I would consider a successful protest in the US.
It's plausible that the feedback mechanism of social protest has been severed from policy for the last several decades. (again, I don't have evidence of this, and would appreciate input from a political scientist / historian / someone older). It also plausible that protest is no longer successful due to a plethora of reasons, such as the absurdly high quality of life / cunning adaptions of policy makers / new communication technologies / or that our government has actually improved. After all, we have a volunteer army and have ended Jim Crow.