i just randomly choose...i don't really care...i go for personality not for looks...most of the time ^^
Mostly it's people that I already know -- otherwise I'm pretty selective about who I add.
I do like Jacob's answer though! :-D
I am very picky and I do have a list of things which are important for me to accept as a friend – should have a good taste for music, funny, open mindedness and lot other good qualities.
The first thing would be seeing whether I know them as a person or at least I should have seen them at least once.
Humour sense always stands out to be the first option where as if they talk interestingly and if they give me wonderful answers to the questions asked I would certainly add them.
course I would go for the person having sexy and HOOTTT avatar picture!
That person needs to be funny and deliberant in every way.