I am familiar with a fair number of forums on-line and have even set up and run phpBBS forum and Toast forum software, so my observation is that this forum is about average or normal for response time to user input.
Some forums, such as Camcorderinfo and the huge AVS forum are understandably a little sluggish. However, recently I started browsing a bit on the DVInfo.net forum which is quite large and I am very impressed with the response times. I am quite currious what they might be doing to get those snappy response times and whether it costs dearly or not. Obviously, I think this would be valuable information.