Xur agent of the nine only appears on the weekends (Friday-Sunday) with exotic stuff. He is located next to the crucible vendor...hopefully this weekend will find out if he has new supplies, I would hope so. Not everyone has enough strange coins or mote of light so coming in on the weekends gives us a chance to stock up on coins. Plus remember you can only equip one piece of exotic armor and one exotic weapon so being a very limited black market vendor really forces the player to choose and choose wisely 9n what purchase you want to make..just my thought