Ohhhh - you opened a can of worm! It's like asking if you're a democrat or republican! Notice, I used small 'd' and 'r'.
I like asymetry and rectangles, but some square wall hangings appeal to me. Sometimes, a square is what you need, as someone pointed out for a king size bed or a queen size with the overhang. It depends on where the quilt will be used.
So I guess I'm both!