I had a closer look at the cover of the drive in your first photo. There is a “WDT1822” ID on the label. This suggests that the drive uses the 2060-771822 PCB.
http://ep.yimg.com/ay/yhst-14437584971410/2060-771822-003-7.gif
According to the following PCB supplier …
… this board is used in the WD2002FAEX-00MJRA0, WD4003FZEX-00Z4SA0, and WD2000FYYZ-01UL1B0.
Notice that the HDA connector (J1) has 22 pins whereas your 1TB drive has a 20-pin connector. I suspect that the extra pins would be required by the piezo element in the dual actuator that is present in the 2TB models but not in the 1TB.
I wonder if your photo is a promotional image that has been incorrectly PhotoShopped by WD’s marketing people. BTW, the model number suffix identifies the customer code (eg retail, Dell, HP), family, and version…
