Got the HD 700's today. They look great in person. They are smaller and lighter than the HD 800 and are ridiculously comfortable. I had them on for 2 hours in one sitting and adjusted them like once.
Didn't expect to like them as much as I do. They ain't no HD 800, but they are a completely different beast compared to the HD 650 as well. Treble sounded slightly metallic and artificial at first, but after a few hours with them I really began to appreciate their incredible imaging and fun presentation. They really shine with rock/acoustic music, I kept wanting to turn them up louder.
I could see them not being everyone's cup of tea, but personally I'm pleasantly surprised. I like them a lot.