According to this link from Rivals.com Auburn has offered the defensive coordinator position to Will Muschamp.
We've known Coach Boom was the number one choice for days. The only real update in this story is word that Auburn has made some form of offer. Now Auburn waits and sees what he wants to do.
Muschamp is also holding an offer from Texas A&M and "provisional" offers from NFL teams according to that article. It could end up in a bidding war, but I really don't know that it will come down to money. Auburn will offer Boom enough money to make him more than happy. I think it comes down to what type of offensive team he wants to coach alongside and how much he likes the town and school.
If it comes down to that second part, I think Auburn is a lock. We know he and his wife loved their time in Auburn. We know his wife is from barely an hour and a half away from Auburn.
So, the offer is out there. Now we wait. But as the article points out, Auburn can't afford to wait too long. It matters to recruits.
Phillip Marshall from Auburn Undercover made a great point by saying Auburn can't install a new defensive scheme before the bowl game, so it's unlikely the new DC would run the defense before that game, but I'm willing to bet Coach Malzahn still wants a DC in place before those practices. Bowl games are exhibitions and the season is already over for all intents and purposes, so it would be crazy not to use those extra practices to begin putting in the basics of the new system.