Honestly, even if I didn't like Moonkin form, which I love, in a raid that consists of 20+ people, I like being able to easily identify myself in what can be a cluster at times. Other than that, during raid encounters, dungeons, I am not worried about what I look like, I am way to focused on the actual encounter itself and everything that needs to be avoided, focused, dotted, and other responsibilities.
In the end, moonkin form is unique, of the 36 specs (i think that is right) in game, we are one of a few that has a unique permanent shapeshift. If you weren't i moonkin form, what would your xmog be? some tier that all other druids think looks cool?
Give me moonkin form. I am Balance Druid and proud!