friendship experimentation

by virtue of study-travel, i've forged several new friendships in the past couple of years.

i am fascinated by the flow of human conversations--how topics are broached, what opinions are shared, and what stories are told. add time scale to this and it becomes evermore intriguing. i wonder how one can chart the development of familiarity between two people--how do topics of conversations change as familiarity and comfort with someone increases? the quest for an answer could take the form of an interesting experiment: make a new friend and record all conversations.