"A league source tells us that Nolan curently is in the process of lining up a staff of assistants, and the thinking is that Nolan will be the next defensive coordinator of the Packers."
49er fans are happily looking back at the free agent signing of QB J.T. O'Sullivan because it led to the canning of Mike Nolan. So that is not a ringing endorsement. He did a lot of damage to the 49ers when he was acting as their GM from 2005-2007, but not necessarily due to his defensive coaching. He also was a PR disaster, especially when talking about QB Alex Smith.
He's got a solid resume and been on the NFL sidelines every Sunday for the past 20 years. Maybe we should worry about whether the current players would fit into the scheme Nolan prefers, but I honestly don't know that much Xs and Os to say.
It doesn't matter who the defensive coach is unless he has players who can get the job done. And GM Ted Thompson has to do something to reload the roster in the defensive front seven for whoever the next defensive coordinator is. The selection of the new defensive coordinator is not as important as free agency in March, and the draft in April.