The headband looks... cheap.
The cups, well... They still look like they belong on the ears of flight controllers on board a star destroyer...
And a big photo here:
And don't get disappointed about them being too easy to drive - these are gonna require a little bit more voltage swing and more current than the HD 600/HD 650:
Nominal impedance: 150 Ω
Sound pressure level (SPL): 105 dB (1 kHz, 1 V)
Correction: I was going off of Sennheiser's cut sheet for the HD 600 which gives a sensitivity of 112 dB (at 1 kHz, 1 V). It appears that number is a typo/incorrect and 103 dB (at 1 kHz, 1 V) is the correct value. (Many thanks to khaos974 for pointing this out.) So the HD 700 will need 80% of the voltage and 160% of the current that the HD 600 needs, based on nominal values anyway.