The playing with section will be an icon next to the team, communities, and game section underneath the stream that allows other streamers (perhaps a limit of 4?) to be tagged, and when you click on their name it takes you to their channel. This makes it easier for people to identify who streamers are playing with, and so they don't have to ask in chat. It also helps streamers with networking.

There can be an option in the streamer dashboard with a box to type in the streamers name.