I'm going to necro this thread, cause it's such a good one.
I think that metal is one of the greatest music genres in existence. While most other music genres is very much restricted, metal can just be about anything, or almost any play style. Different metal sub-genres has the ability to inspire, and make you feel a wide range of emotions, be it inspiring, happy or jolly, sad or melancholic.
I can't imagine my life not listening to metal. Metal has been there in hard and happy times and it has helped me come to terms with anger and sadness. I regularly listen to metal, pretty much every day, and if I go over extended periods without listening to metal I can get pretty grumpy and negative.
"Without music, life would be a mistake." Friedrich Nietzsche