Thumbing around the forums you can see a number of different threads; and why all have different topics they all have the same answer. A in game player rep system.
What do I mean? Just like the forum rep you can add to or remove rep from a user. But I have some guide lines.
1, Rep is account based. This way someone can’t just jump to another character and have a clean slate if his/her rep falls low.
2, Rep modifiers falls off after 30 days. Any rep gained or lost at 31 days or older is removed.
3, You can only mod rep for some one in your party and only once a quest. When rep is changed a message shows on screen letting you know that is has been changed and the value of the new score. Maybe only once in a 24 hour time frame. I am not sure on how often you can add to a users rep… if you quest with the same guy 3 or 4 quests in a row and he is super helpful and what not each quest you might want to give rep to that user during each quest.
4, If no one changes your rep in a 24 hour period that you have played and grouped you get a free bonus amount of positive rep.
5, Your rep total can been seen by you, and group leaders only. Group leaders only see your rep total when your applying to a group.
6, When you give neg rep you also take a point of neg rep. So you better mean it.
I don’t know if this would really help but it would allow me to clear a lot of room on my “friends” list. And would maybe get me to (lead) group more by help me filter out some of the undesirables. Your reputation would be right there for others to see good or bad.