More to follow....
Right off the bat (zero burn-in) with a quick A-B over my LCD-2 Rev. 2s, improved soundstaging, tighter bass and cymbals seem alive (truer to real life than either the Rev. 1 or Rev. 2 LCD-2). So far....more evolutionary than revolutionary like the LCD-2s were (but definitely noticeable and enjoyable).
About the same weight, but just slightly more comfortable than the previous versions due to the softer ear pads. Not way more comfortable....slightly I would say (that's with 15 minutes on my head).