Well, among the candidates that the Atlanta Falcons still want to interview for head coach is Giants defensive coordinator Steve Spagnuolo. But because this would be Spagnuolo's first interview with the Falcons, Atlanta can't speak to him until after the Super Bowl (teams can bring in coaches for second interviews during the current week).
Atlanta couldn't get Spagnuolo for an initial interview right after the regular season ended, because the Giants were in the wild-card round and New York didn't have to grant permission for the interview - and did not because the Giants felt it would be a distraction.
Meanwhile, Rex Ryan, the former Ravens defensive coordinator, is also a candidate for the Falcons job. After hiring John Harbaugh as head coach, the Ravens said they'd like to retain Ryan as defensive coordinator. But if Ryan's status can't be cleared up because the Falcons' head coaching search is on hold, that means the Ravens' staffing plans are likewise stymied for the time being.
See, this is all Bobby Petrino's fault.