The absurdity of an "atheist movement"
For any mass movement to emerge to prominence and come to be accepted by the average man, it must impose its moral necessity, and it must have the means to manifest itself.
The movement to strip kings of their power and replace them by a sprawling bureaucracy both reflected a presumed moral necessity (to give "the people" power instead of an arbitrary king) and had the political and military means to manifest itself. So, unfortunately, it succeeded.
The anti-slavery movement reflected the moral necessity of abolishing the extreme inequality and classism entailed by slavery, and through difficult and long travails, came to fruition, toppling an institution as old as civilization.
The modern "environmentalist movement" has been tremendously successful because it took a widespread moral malaise of the modern man (that he lives in an "inferior" state to that of nature, that technology is vaguely dangerous) and turned it into a movement which fuels itself by scaring people. So far, it works.
Any assumed "atheist movement" has neither of these qualities. There is no perceived moral necessity in spreading atheism; rather the contrary, as most people believe atheism to be immoral, even atheists themselves. So far, the only "cause" atheists have latched on is the separation of church and State, which, apart from being a ridiculous idea, already failed a century ago and is no longer an ongoing concern. The relationship between the State and religion has become too subtle to sustain moral outrage. It is a stillborn "cause."
As for means, well... a few YouTube videos are not going to cause a revolution.
Hopefully the self-important bloggers (who are also just as insignificant) who rant about the Blasphemy Challenge will stop hassling teenagers trying to express their identity, and turn to more productive things.