I could take pictures, but Tyll has already done this, so for simplicity's sake:
Picture in question: http://www.innerfidelity.com/images/Denon_AHDx000_photo_differencescloseupbig.jpg
The left side shows the old model, the right the 2012 production model. So to find out which you have, you'd just have to remove one of the pads.
Hmmm... Your statement on the D2000 being lusher is interesting. After extensive auditioning of warm lush cans like the hd650 and lcd-2, the d2000s sounded drier for my tastes. But mind you, it was a side-by-side comparison so YMMV. But Tyll at innerfidelity has also mentioned the D5ks have a much lusher and warmer sound, and the d2ks being the driest of the trio. I think you are the first to mention the D2ks are warmer than the D7ks. Btw, I only did a D5k vs D2k.
EDIT: Get it now, it was the pre-2012 model. Tyll was comparing the 2012 Model of the D7ks and D2ks.
Hm, sorry to confuse. I think I misused the word lush. It's rather hard to describe the differences between the mids on my D2000 and D7000, but at the same time I think it's important to, as they're quite different.
I've since listened to the D7000 more now, and after hearing some female vocalists, I can say the female vocalists certainly sound more lush than on the D2000. Otherwise, I think I know what I meant by the D2000 sounding more lush when I wrote that late last night. So here goes my best attempt at clarification:
The D7000 vocals are more forward and have more weight and presence. Now, if those are the qualities that make up a "lush" sound, then there you go - the D7000 is more lush. However, I will yet clarify what I meant by the D7000 sounding dryer. The D7000 vocals are quite a bit clearer, better separated, better defined, and more distinct that the vocals in the D2000. Conversely, the D2000's vocals seem a bit blurrier, less tight, less defined, less separated, and thus more seamlessly integrated with the overall sound image than on the D7000. Because of this, they seem to "mesh" with the looseness of the lows just a touch, which I feel lends to a slightly wet, lush sound in the vocals. This seems more evident with male vocals. With female vocals, I can certainly see the D2000 being described as dry sounding.
So...hopefully that didn't make matters more confusing. In short, I think I perceived the looser, less distinct, and less clear vocals of the D2000 as slightly lusher sounding than the D7000.