I heard the "100" figure also, but will only remark that at the time _I_ did a crowd count I came up with approximately 40 (+/- 5) on our side, and roughly 30 (+/- 8 on theirs). I'm no expert at this, but there are some simple procedures that can get one into the ballpark and I double-checked my numbers with another engineer there. After that our corner was "invaded" by some libs (some of whom I don't think were really quite aware they were on the wrong corner, and some who definitely were) whose appearance seemed only to increase our numbers.
About the time I left, a quarter to six, the numbers were approaching parity and I saw a number of libs walking towards the demonstration.
An after-action report over dinner from LibreOuMort and friend tells me I left at the nadir of the action. Things apparently got pretty lively after, with more turnout from the Fighting 570th, and our friend who'd never been to a FReep before was excited about it all.
I should have some pictures for you all tomorrow.