The article from MIT Technology Review mentioned in my previous post referenced a paper from Nick Yee & Jeremy Bailenson titled “The Proteus Effect: The Effect of Transformed Self-Representation on Behavior”. The researchers found that appearance of avatars shapes the behaviour of users:

[…] self-representations have a significant and instantaneous impact on our behavior. The appearances of our avatars shape how we interact with others. As we choose our self-representations in virtual environments, our self-representations shape our behaviors in turn. These changes happen not over hours or weeks but within minutes.

A copy of the paper can be found here.