Matchmaking for fireteam activities? Sort of. Soon.
Bungie is sort of doing something about Destiny raid LFG
Destiny: The Taken King is in pretty fine shape after the April update, with lots to see and do, and many delightful rewards to earn.
Unfortunately a lot of the best stuff is still locked up in fireteam activities. Challenge of the Elders and King's Fall both require pre-formed fireteams, and even Court of Oryx is a bit of a pain if you don't get lucky with your instance.
What's a solo guardian to do? Bungie has long maintained that it wants communicative, pre-formed teams to tackle these activities rather than match-made randos, and that it expected the community to produce tools - but it's going to make things slightly easier, and a bit more official, by way of a companion app update.
When the update rolls out, the #Recruitment forum on Bungie.net will be overhauled with extra functionality, making it much easier to find and join fireteams via your second screen. In a preview shared in the latest Bungie Weekly Update, you can see fireteam posts showing platform, tags and how many slots are left. Filters will allow you to search for specific types of groups by activity, platform and certain tags, and you'll be able to make your own posts right from the app.
Unfortunately, you'll still need to manually add fireteam members once you've found some. (On PS4, the easiest way to do this is to set your fireteam to open, start a party with your fellow Guardians, and then have them click join game in the Party screen. That way you don't have to add them to your friends list if you don't want to.) It's not a perfect, smooth matchmaking experience, but it's the first "official" LFG tool we've seen Bungie support, and it could be very helpful.
Personally I'm a big, big fan of The100. I don't play as much Destiny as I used to, and I'm pretty shy about strangers, but I've had nothing but good experiences teaming up with Guardians over there, which is why we were so excited to partner up for The Division The100.