We may have hit our player max of 200 the beta guild was set to in doing a quick test of increasing past 100. We also did not hit the 200 cap until last Friday's beta test some time in the middle of that four hours. The first time we could play with increasing guild size was BWE3 in July, if my haphazard memory serves me right.
For live it will take coordination to do the guild level increases and it will take having the leader, Fog, on. I don't think anyone other than the leader can do a guild size change. I know to go from 100 to 200 it took some money we pooled (forget how much) and the need for 20 members to be online and representing the guild. The amount of money and number of members online to push the guild size up increases with each step of the process.
So when we go to live and Fog says he needs people on to do this and you can be on, please be there representing or be square! Hehe. Just my plug to anyone reading this to help us build up guild size as best we can. Based on number of players for beta and stress tests, we'll want at least 300 as fast as we can do it, since that is just over 200 now and I know some people who pre-purchased but might not make it on for the final hoorah of stress tests.