Ok, I played on Graffiti for a while today (well, didn't actually play, just observed in the background since I was at work). There were no lag spikes for a long time, even with 25+ people. Several people had come and gone. Then two people connected with build 18 at the same time and there was a lag freeze for about 2 seconds, server side. I think it has to do with the DNS resolution of dplogin.com, since the UDP packet sending should be instant. If I cache the IP, then it should make those lag spikes go away.