I have recently upgraded to Drupal 4.7, and it's fantastic. However, the Project module upgrade didn't work (probably because I use Postgres) so I've only just got round to installing it again.
To celebrate this, I have made a new release of my GeSHicodefilter Drupal module. It is now Drupal 4.7 compatible, and merges several enhancements from Vince Filby's geshifilter module.
PLEASE NOTE: A derivative of this module is now maintained on drupal.org, at http://drupal.org/node/65961. Note that the syntax has now changed from "<code lang=..." to "<blockcode type=". Although I'm not totally happy with this change, I feel it's best to stabilise on the newer format rather than having a syntax war.
I couldn't find a Drupal module to syntax highlight C# code, so I made one. I'm using the Generic Syntax Highlighter, GeSHi, to drive a filter loosely based on the codefilter module. While doing this, I discovered Nonstop Bits' Nonstop HiLighter module, which highlight many more languages, but I think GeSHi produces prettier output colours :).