This site launch marks quite a few firsts for me. Although I've worked with the technologies before, this is the first time I've launched a site running memcache, Varnish, and Apache Solr that I've set up myself. For a little bit of context, memcache and Varnish both help boost the performance of websites and web applications. Memcache caches objects in memory to reduce database load, while Varnish is a reverse-proxy HTTP accelerator that essentially caches the contents of webpages, keeping load off of the webserver (in my case, Apache) itself. Apache Solr, on the other hand, is a search platform that offers more advanced searching than Drupal core (e.g. faceted searches) and can also help with Drupal's performance since searches are no longer run against the application's database. All three of these will prove useful in creating scalable, useful web applications in the future.
This site also uses my first Drupal 7 theme and custom module. I was really surprised at how many theming changes there have been in Drupal 7, but all of the changes seem to be positive. The custom module I wrote is really tiny; it implements hook_admin_paths_alter() to turn off the administrative theming on user pages, which did not look very good.
The site isn't quite as complete as I wanted it to be prior to launch, but it works. It will give me a place to document my progress as I experiment with Drupal 7 and its community-contributed modules and continue creating my own custom modules and themes. Moving forward, I'm going to work on creating a responsive theme with HTML5 markup for the site (it's sad that there's nothing mobile-friendly here yet), tweaking the Varnish configuration to increase cache hit rates, and adding new features and functionality for experimentation. I will try to write up this information in a friendly tutorial-style format to help others who are working on implementing similar features, and I'm going to work toward contributing my own unique developments back to the Drupal community.