As expected, the Broncos have named Jack Del Rio as interim Head Coach this morning, while John Fox recovers from his heart surgery. Del Rio was the head coach in Jacksonville for nine seasons, and compled a 68-71 record in the regular season, and 1-2 in the postseason. That's pretty solid work for an organization that was consistently under-resourced, especially at the QB position.
Del Rio is expected to continue in his duties as Defensive Coordinator, and I don't think he's ever done both jobs simultaneously before. As Andrew Mason said this morning, the high degree of experience on both the coaching staff, as well as at some key player positions, should assist Del Rio with the double duty.
While I probably would have made Eric Studesville the interim Head Coach, it's hard to find much fault with the choice of Del Rio. I generally think it's less disruptive on game day to have the running backs coach doing other stuff than he usually does than it is the defensive coordinator, and that Brian Callahan could fill in for Studesville with the backs, as he's done in the past.
We should probably assume that the Broncos will figure out the best way to work the mechanics of it all, as they've done an excellent job all year of adjusting to injuries and other obstacles. I don't think that Del Rio will represent any less conservative of an approach than Fox did, though; as old defensive guys, they're cut from very similar cloth.