DrupalCon — there's hardly a better time or place to try your hand at contributing to the Drupal project. Yesterday I went down to Wunderkraut's contribution lounge to see my good friend and colleague dixon_ and ask him for advice on where to start with code contribution. He showed me an easy way to dig right in by reviewing other people's work using sun's Dreditor user script, and I was so excited (it's much easier than I thought!) that I couldn't resist sharing it with you as well!
Did you know that NodeStream changed from its initial intention to be an online magazine publishing distribution? This is something we at NodeOne have worked on for a while and internally we actually use NodeStream as a base for all our client projects. We think NodeStream is mature enough to become a base for more peoples project and we plan to support you with it.
On NodeOne we use Features a lot. Mostly for exporting configuration, and we have some problems with that. Some of the stuff that you want to do, is not in Features, sometimes we need to solve it in another way - mostly with code in the installation profile, but some other issues just keep hanging lose.
You should work with coding standards in mind, it is a very good thing when you share you things with other developers. And there tools out there to help you with the standards, for me that is the Drupal Coding Standards.