Sounds about right. The Paizo booth was my last stop before leaving around 2:30pm or so on Saturday, and they had about 100, maybe 125 copies left; just a quick guesstimate.
The Thursday line was incredible, with people carrying multiple copies to purchase (they had a sign limiting people to 6 copies each - for a $50 book!). To their credit, it looks like they worked through the line as quickly as they could, because by the time I wandered over to get my copy around 1:00pm, there was no line.
The big "pyramid" of books was restocked periodically. The big table they were on was packed with more boxes of books. When I left around noon on sunday, there were still plenty on the table.
The big "pyramid" of books was restocked periodically. The big table they were on was packed with more boxes of books.