Social movements don't need to be quantifiably better to take off.

When the relevant audience is bored enough to be open to something new, it only takes a few influential people to tip the scales.

People don't want to be truly revolutionary; that takes actual risk. They want the appearance of being revolutionary with minimal downside and social reassurance.

(w/r/t GitHub there's already enough buzz in the right circles and it will likely happen this year.)