I got tired of seeing old pre-BC styled icons mixed with BC and WoTLK icons so I decided to batch process all the icons into a clean format. 6,296 Icons have been altered.
This may seem like a large filesize, however this does not use any cpu usage or additional memory usage than simply running without it.
This also extends to any addon that uses the default game icons such as Power Auras Classic.
Example Pre-BC (Rounded edges no border highlight.):
TO
Example BC (Black corners):
TO
Example WoTLK (Added a black inner glow and a sharper border highlight):
TO
Install to Interface > Icons
Before and After:
Power Auras Example: