Picture yourself in a larger group...say 10+ people and you're a healer. I think before, you could not drag the characters names out of the raid window so that you can always see their health without a mod. Now, you are able to do so without a mod. .jpg could answer that better, but I know there will be some mods you would want even without pvping.
I can say from a pvp standpoint, the mods give me an advantage. It's slight, but I consider myself tougher to beat with the mods than without.