In September of last year, I was invited to speak at WordCamp LA on developing fast and scalable servers for WordPress. During the 30 or so minute presentation, I covered quite a few topics. I strayed away from the application layer side of things and really focused on server improvements and software considerations that offered the most performance. I got some really nice feedback and met some great people involved with WordPress in the LA area. The two other WordCamps I attended before (New York and their flagship conference, San Francisco) were extremely well organized and WordCamp LA was no different.
Although I wasn't able to post my slides, I've posted the video here. I look forward to speaking at more events like this and I highly recommend attending a WordCamp event if one comes into your town.