Drupal.org is a bit painful to browse on a mobile device. It'd be cool if it used responsive design to show off what Drupal can do!
Our current http://drupal.org/cases section is very sad. We should make it show off how awesome Drupal can be with pictures, how-tos, case studies, and more!
Move job postings out of groups.drupal.org and onto drupal.org, and improve the listings with ties back to companies and locations + featured listings to help fund d.o development.
Show upcoming events in your area, show what events people are going to on their profile, show a map of events around the world, etc.
The current Drupal Services listing at http://drupal.org/drupal-services is just a bulleted list of companies in alphabetical order. A better listing could allow people to search by country, business sector, and could also prominently feature companies that give back to the project.