All four items that Xur brought with him for the weekend are new Exotics from the Curse of Osiris expansion. This will provide you with an exotic armor piece that you don't already own.
Let's take a look at what he's got.
Xur is in the Winding Cove. Just jump up to find him standing next to a crashed Fallen Skiff. It doesn't actually shoot grenades, though, as its payload is tiny robot insectoids. The Shinobu's Vow Hunter gauntlets are available for 23 shards. It costs 29 Legendary Shards. In fact, they all are. If you're prone to dying, it might be worth equipping this so that your team members can get a bit of a healing boost when they come to revive you. 44 Stand Asides, which are boots that grant you an overshield when sprinting at full health using any of the three Titan subclass charge-melee abilities, like Shoulder Charge. Any hits with those melee abilities will recharge a portion of the melee ability charge.
Screengrab via Destiny 2
The vendor will also sell Fated Engram for 97 Legendary Shards.
This week's Warlock armor is The Stag, a funky-looking deer helmet with long antlers.
Xur has brought with him the Three of Coins to help you get more exotic drops as you play the game, and he's got something called the Fated Engram, which is guaranteed to give you an exotic weapon or armor piece that isn't now in your collection.