Just a quick opinion after some time with the Rev 2 LCD-2's: I don't care what the graphs say--to my ears, the Rev 1 and Rev 2 sound less alike than the graphs might suggest. I don't know if it's due more to the earpads (both of my Rev 1's are equipped with the older style pads, and I haven't done any swapping yet) or the different drivers, but the LCD-2 is noticeably more resolving to me, and the improvements in tonal balance and treble presence are noticeable and appreciated (for my tastes). I'm over the moon about the changes.
I still love the Rev 1, and the ones I've got aren't going anywhere. But if Audeze had asked me what I'd change about the sonics of the Rev 1, the Rev 2, as it is, is what I'd have asked for.
On the one hand, I see why Audeze has stuck with the LCD-2 designation for this revision. On the other hand, part of me is surprised this didn't end up being called the LCD-3.
(And, yes, I have both sets, so I'm not comparing from memory. I actually have two sets of each; and, again, I'm keeping the Rev 1's, as its signature is still an awesome flavor to keep around.)