A custom CSS for the emoticon legend
You can get the style from userstyles.org
(preferred, allows updates) or you can hit the download link on the left and paste the contents of the file into Stylish.Stylish
is required to install this style.
Edit: Updated the style slighly in order to get a bit more v7-ish look
Edit: Something changed, now somewhat fixed. Thanks for the DD
Edit: They finally updated the emoticon legend styles, so this userstyle has come somewhat obsolete. It still works, but I won't be updating it anymore as the default styles now look quite nice