I just leave the "Top Friends" list alone. I don't really like the idea of categorizing or classifying my friends.
The people on my top friends list are usually the ones who message me lot, ALWAYS comment or rate on my stories and quizzes, and I enjoy lots of their quizzes and stories.
If I consider them a close friend! If we talk a lot and such, I put them in my top friends ^-^
I do it by who has the coolest profile pictures :)
If we get along with each other, message, and have common interests, then I do :P
I don't use top friends.
I put them in my top friends if they awesome, really nice, and message me alot :D
I put the people I enjoying talking to most in my top friends. It's rather hard actually, because I have 20 people that would qualify as my top friends but I can not fit them all.
Sadly I don't think I'm on anyone's top friends.
If we message each other a lot, they're really nice, funny.