Bungie brought Xur back for another weekend of Exotic-a-palooza and he is carrying some rather useful items, possibly in an attempt to apologise for Aeon last week.
Xur can be found in the Tower this week. To get to his location in the hangar, pop up in the Courtyard, put a marker on Amanda Holliday, go to her and then turn left towards the platform where the aircraft lands. Proceed that way until you spot Xur on a catwalk to the left, as pictured below.
He is carrying Hard Light this week, a fantastic weapon for both PvP and PvE. It has lost some of its edge in PvP since the nerfs in Season of Arrivals but it's definitely still a potent weapon. This auto rifle can hold a corridor without the Guardian ever having to peek out thanks to Ricochet Rounds and the projectiles will pretty much scare off anyone who though about rushing you. In PvE, it can be invaluable for breaking shields thanks to the ability to change element type.
Hunters are getting Khepri's Sting which is extremely useful for niche builds in PvP since it allows you to have wallhack with low cooldown time. Pop a smoke, see enemies through a wall, kill them and if you brought Gambler's Dodge along, you will be able to do so again almost immediately.
If you feel like your Titan needs some mobility, you either pick Dunemarchers or Lion Rampant. It is the latter that Xur is offering this week and it's a straightforward Exotic - gives you an improved lift and air manoeuvrability. You can bring it along in PvP to outpace the opponents or in PvE to speedrun strikes for those pesky bounties.
Warlocks are getting Phoenix Protocol. It is specifically tailored for the Well of Radiance users and doesn't work with any other spec. But boy does it work with the Well. Pop the Super and watch as the energy surges back with each kill you or your allies inside the well score. The Well is fantastic for running Nightfalls and this Exotic makes it even better.