Overview

To update:

wget http://200okconsulting.com/safari-extensions/CleanYouTube.safariextz
xar -xf CleanYouTube.safariextz 
cd CleanYouTube.safariextension/
for i in *.*; do echo $i; diff $i ../$i; done
# deal with whatever changed, probably just by cp-ing
cd ..
rm -rf CleanYouTube.safariextension
zip clean-youtube.zip clean-youtube.css clean-youtube.js icon*
jquery-1.4.2.min.js manifest.json

or maybe zip -f *.zip *.*