The NFL is a constantly evolving league, and this fact usually brings many positional changes from year to year. In the '70s, it was run first and pass questions later. In the '80s the innovative West Coast offense was all the rage. The '90s was dominated by a well-balanced powerhouse known as the NFC.
The new millennium started us off with defensive dominance, but that didn't last very long and gave way to the pass-heavy palace that we all inhabit these days. The QB has been the most important player on the field for decades, but teams didn't necessarily have to have a Pro Bowler caliber passer to be considered a contender.
Now it seems if a team doesn't have a QB who can throw for 3,500 yards, they may as well pack it in and wait for the next year to try again. Having said that, a quarter of the league is still making changes under center, whether due to injury, choice, or necessity. Here's a look at the teams in transition in Week 6.