So I got to finally hear a pair of HD700s today. They were surprisingly better than some would have us believe. They did have more bass and treble than the HD800s. They weren't as quick, more "U" shaped, BUT they still sounded quite good. The treble though could get on one's nerves over the long haul (or not I guess, depends on the person, but I'm thinking with me, over time it would get to me). I liked the added bass weight. They were very clear and expansive sounding (though not HD800 clear/expansive). They were quite a bit better than the HD650s that I heard them with them.
Comfort wise, they were among the top 3 or 4 headphones I've had on my head. The HD800s are still tops for me, but these were admirably good. Construction was sold, the cabling was quite good and they looked/felt like high priced headphones.
Overall I liked them. Where they perfect? Nope....a bit too much tizzy treble and bass performance could use some improvement (in terms of control and clarity). For the money, I'd take a pair of LCD-2s or used T1s any day of the week though. But I can certainly understand how/why someone would like them.