The guys at Together for the Gospel are modeling something VITAL:

"Something that is meant to be different about the T4G conference, and what it may inspire in your own ministry, is that it is built on, and attempts to model and provoke relational networks for encouragement and accountability. So inviting Thabiti was no mere decision of the 4 of us to send him a letter. First, we had to work at building in relationships, and introducing Thabiti to the brothers who didn't know him. So the delay in announcing his speaking reflects nothing on our confidence in him, but rather highlights the different kind of conference this is. From the moment the idea was born, time would need to be set aside for fellowship together and co-laboring. That has now largely happened. And we are delighted not simply at Thabiti's agreement to speak, but at Thabiti's growing friendships with the other speakers involved in the conference."

— Mark Dever