I just upgraded the site from Drupal 6.3 to 6.9.
Wow.
I'm so exhausted. It took me a couple of hours. What happened was that I discovered that I'd mixed the custom modules with the core modules, so not only did I have to go through the Indian rain-dance, I had to re-upload the GeSHi syntax highlighter via FTP (God, that was slow, thanks shitty ISP upload cap!) plus all of my modules.
Not fun.
I changed the colour scheme because I was getting tired of tan brown, proving to myself that I don't have any design sense. Ugh.