It seems the United States leadership has somehow weathered this mass uprising and survived to govern another day.
Most people report 30~ OAS people, though one of my local contacts did say that after 20-30 minutes of searching they found a group of around 200~, in an out-of-the-way location where they really weren't engaging anyone (contact's comment: "They were the worst protestors I'd ever seen.").
This number seems consistent with one of the leaders of the Operation claiming to have come up with over a hundred people, so I'm inclined to believe it.
As one of my other online contacts says, 'They wanted to drive more people out office than they had protesters at the rally.'
Reasons for the low turnout, well below the expected 10-30 million, is cited as heavy rain this morning.
Gawker article with photos Washington Times report: Operation American Spring Fell Flat