I recently purchased a new 13" MacBook Air (which is a truly wonderful machine). Before I booted the machine for the first time, I started to contemplate what was needed for the machine to be setup for my development needs. I have, regrettably, avoided keeping track of what my environment looks like. I decided to change that. I have started tracking my environment setup on a static page on this site. It may not be the ideal setup for everyone, but I have found that it is the bare minimum of what I need (it is a work in progress and I plan to keep it updated as my methods and needs evolve).
If you have any questions about my setup, please feel free to ask.