The community seemed rather unanimous though. We want little, sharp-toothed, creepy, ankle-biting cannibals.
As for Orcs, they haven't changed much besides going from hostile baddies to citizens of the empire and receiving a deeper history. But, their appearance has remained the same throughout the eras. Green people with pig snouts and boar-like tusks. Except that there were no tusks in Daggerfall, and Morrowind added a couple of unique, little features. The different looks can be chalked up to art style and graphics, in my opinion, because they all represent the same thing. Human head, pig snout.
For the smaller features, some of the orc females in Morrowind had these sort of decorative ridges on their foreheads cheeks and chins. Not all of them, though.
Also, in Morrowind, all the hairstyles were almost exclusively ponytails, for both genders, except for like two, and they had really over-exaggerated baggy eyes. They always looked really tired.
My very first character in Morrowind was an orc. He got owned by the Urshilaku burial caverns a bunch of times, so I gave up and made a Redguard. What do you think of the Orcs?
Here's a little http://www.uesp.net/dagger/monsters/morcs.jpg Orc from uesp.