The uncanny valley has even led studios like Pixar to shy away from human photorealism, instead choosing cartoony stylization (like the characters of “The Incredibles”). The uncanny valley especially worries video game designers, because their animations are rendered instantaneously, without time for careful staging or touching up.
You can read more about the “Uncanny Valley” at http://en.wikipedia.org/wiki/Uncanny_valley
Surprisingly enough, some natural language vendors, chat bot producers, and self-service specialists seem have not learned this lesson, and they use some human-like implementations with very scary looks, that fall completely into the “zombie” category, such as the ones shown above...
At Inbenta we have partnered with several companies that create 3D-animated avatars, and the conclusion is always the same:
if you plan to use an avatar, chose a good one!