We've been wrestling with some performance issues. In order to rule out any system file corruption I will upgrade us from 4.1.7 to 4.1.11 That in itself has over 600 bug fixes and performance enhancements in the core software. The APUG theme coding is in need of updating as well which is a big job. You may notice some odd appearance to APUG while this is worked on.
Ultimately I think APUG has reached a point where more focus needs to be placed on performance and stability. One problem with custom themes is that old codes often persist after upgrades. I may try to move us closer to the standard vBulletin theme to always ensure we are running the latest codes. It may not be as "pretty" but it will make for a much faster site. This will also allow for simplified updating.
Stay tuned and thanks!