Two things coincidental with the 'out of thin air' bit: 1) There's no signs. No banners. No uniform. No unifying symbology like the Green protests of 2009. Hordes of young people with cell phones held high.
2) There's no obvious leadership. A few people on the outside speaking up in support, but there's no one specific in charge that can be arrested. Its all decentralized.
We've seen this before. Kirkuk. 100,000 people fled their homes based on rumors, entire Kurdish militia just up and ran right along with them.
Someone somewhere figured out how to use social media and word of mouth to get hundreds of thousands of people to do something in unison. Protest. Riot. MOVE.
We can't see who's doing the pushing, but we keep hearing of protestors winning in melees against militia who are trained to suppress civilians.
You won't point out what you're seeing, but I'll say it. This scary mother fucker right here and his buddies are using mass social manipulation to hide their own movements. 
Get hundreds of thousands in cities and towns across Iran to rise up, then they move amongst them, protecting them, attacking key facilities, fighting the security forces when necessary. Shooting back when they must.
The Iranians are the ones doing the protesting and chanting and demanding exactly what they want: an end to the Islamic Republic. Scaryface and the rest of his GCC Ghost Army buddies are just easing the way.
