For the sake of answering for everone else. We hit a total of about 80 for 2013, just shy of 100 the year before. This year we have 57 sign ups already and have not yet hit the "last minute rush" when many sign up so I'll wager will be close to 100 again.
We are not a "numbers" event. We do not want to be. I have to fully support every single attendee with support equipment, gear, food, etc etc etc so just piling on the numbers only dilutes the overall experience for everyone. Over the summer, we generally assess the equipment situation and determine what our maximum capacity by side is and make a build to that reflects what our drop dead max attendees number is. In the case of this year, NATO for instance has a max of 65. The Canadian Forces unit within the NATO group has a max of 12 slots with only two remaining open. We tend to have more U.S. Army gear (big surprise) so the U.S. Army has a total of 27 slots with 20 remaining open right now.