Mike McCarthy noted it in his Monday press conference that it will take a couple days to completely evaluate QB Aaron Rodgers after his concussion. He'll be tested by the team doctors, and then have an independent evaluation performed by an outside doctor on Wednesday or Thursday. It's anyone's guess whether he'll play next week.
He also discussed promoting QB Graham Harrell from the practice squad, if Rodgers can't play. That's not a very exciting move, but Harrell has been with the team all season and he knows the offense. He played OK during the preseason, and he has the potential to be as good as QB Matt Flynn. He wouldn't be a disaster if they were forced to turn to him in a worst case scenario.
Unfortunately for the defense, McCarthy said that DE Cullen Jenkins is certainly out next Sunday. They can replace what he can does as a run defender, but no one can replace his skills as a pass rusher. There doesn't seem to be any timetable for his return.