I noticed after I rooted, that Superuser had a black/grey menu background. I removed lots of bloat (Remove Bloat) and decided to add the ones that I use most to system/app/. To my surprise, adding Google Maps to system/app/ led to a Green background. I discovered this by opening the TouchWiz30Launcher.apk and saw that there are dozens of different icon backgrounds. Most apps will end up Black/Grey, but Google Maps at least is the Google Maps Green.