I recently discovered this fellow in my Grimoire
Has he made an appearance in the game yet? I haven't come across this individual yet, so is his appearance triggered by story events?
The wiki says
Xûr sells extremely rare goods in exchange for Strange Coins and only appears on weekends. Xûr's coming and going depends on the planetary alignments.
This seems inconsistent, does he appear every weekend or just when he (Bungie) feel like it?