What is "social"? Everything. Verbal communication is only a very small fraction of our social interactions. Actually some of the best "social" interactions I had in the beta didn't involve any words. One was exploring in The Divide when I was a Warlock running with a HC. I put two headshots into a Fallen Major...and he still didn't go down. He was about to finish me off while I was in the middle of reloading when a Titan swooped in and came to my aid. Put down the Fallen Major with shotgun blast....and kept right on going. The other was on a Devil's Lair strike with a MM fireteam. Our third flaked out on us and never made it into the strike...leaving me and another guy to try to finish the strike as twosome. It was INCREDIBLY hard, and my warlock ended up dying 14 times....ten times in the "mesh" room alone. But both us understood that we were going to stick this out. I wasn't going to quit and let him down...and he was willing to carry me during the part of the strike where my Warlock was very vulnerable. When we finally killed Sepiks, we both there was no dancing at first. We both just sat down as if exhausted after a REALLY long day....then danced a bit and took off. A few hours later there was a friend-invite from him in my message box...and we ran a couple of explore missions together before the beta ended. Bungie will probably include some form of chat, once the game is established and they feel more confident that bad actors won't ruin the game by trolling and griefing. But talking isn't necessary for the social aspects of the game.