If I had to sum up this post I'd say that a post is the start of a conversation. The reply's gauges how that post was received by the individual and indirectly that's a gauge of whether or not the person will want to be your friend.

You can come across as needy, greedy, or insincere if you aren't careful. The basic idea is to take genuine interest in the other person--something that was lost in translation with FB!