The philosopher Plato was quoted saying:

"You can discover more about a person in an hour of play than in a year of conversation."

I used to play an online game named Lineage 2 and there joined a "clan" of players. I knew more about them and them about me in about 3 weeks of play than I knew about people I meet face-to-face on a daily basis. :Þ

They were just more "real" , there was no need to put up walls and pretenses.