It's always nice when you see others have that same idea. The more people that ask for it the more likely it is to be seen as a positive addition, never know what changes theymos will introduce so visibility is always nice. I like the idea of having it in a users profile, and I think I said something about having a pop-up like " You are including/excluding this user. Do you wish to proceed?"
On a side note LoyceV is planning on adjusting the wording on their custom trust list viewer to try and clarify the meaning behind inclusions and exclusions.