These tiers are not based on a quarterback's past achievements. They are not based on "what quarterback we'd start a franchise with" or any future potential. The idea is simple: What quarterback would we want leading our team this year and this year only. Who are the best 2012 starting quarterbacks?
With every team except the Arizona Cardinals settled on a starter, let's break it down:
Rodgers boasts the most complete skill set in the NFL, has terrific continuity around him, and remains squarely in his prime. It's fair to expect just a bit of slippage out of Brady and Brees this year. No one talks about Brees' inconsistent 2010 season, but he's a little more erratic than Brady and Rodgers.
You could call this tier "Hall of Fame." Rodgers hasn't done enough yet to make it to Canton, but he will get there eventually.
It's funny when people write that Big Ben is more about wins than numbers. His numbers are sensational. Only four quarterbacks in NFL history have thrown for more yards-per-attempt, and three of those four haven't played in 50 years. (Rodgers is the other.) Roethlisberger is the best vertical passer in the NFL until proven otherwise.
Newton was a top-10 quarterback as a rookie. We expect a significant second-year leap. We've seen enough out of Manning in the preseason to rank him this high. Only his injury risk keeps him from the top shelf. It wouldn't be a shock if one of these three quarterbacks win the MVP award.
Eli was a top-five quarterback last year. It was the best season of his career, and the amount of low-percentage passes he pulled off will be tough to repeat. This ranking still puts him in the top eight. He's great. Back off. Romo would have a Super Bowl ring too if he played for the New York Giants his whole career. Manning gets the slight edge over Romo because of Manning's mental game.
We don't believe that Rivers has simply lost it at age 30. Cutler can be streaky, but the hot streaks match up with any quarterback. Stafford is similar in a lot of ways to Cutler, right down to the huge arm. Cutler's experience gives him the edge for this year.
Anyone in this tier is capable of winning a Super Bowl, but they can't be counted on to carry their teams every single week like the guys in the two tiers above.
Vick is too unpredictable and injury-prone to rank higher. It feels like Ryan and Flacco are ready to make a leap, but their progress has been slow and steady. I'm sold that Luck can be an above-average starter as a rookie.
Schaub's sharp preseason has erased injury concerns. RG3 figures to have a steep learning curve, like any rookie quarterback. It's fair to wonder if Dalton will take a step back with a tougher schedule. Palmer and Freeman have to pick up new systems on the fly, but we stubbornly still believe in them.
The quarterback position has never been deeper in the NFL. A guy like Schaub would have been in the top 10 a decade ago.
Teams are doing a lot of hoping with guys in this tier; no one really knows. Bradford has the skill set to be elite but he's played like a quarterback with a lower ceiling. Locker has to overcome accuracy concerns. He gets a slight edge over Russell Wilson because of Locker's year in the NFL. Alex Smith is on the perfect team for his skills, but would you want him as a GM?
Cassel lacks great pocket presence. Fitzpatrick can be too aggressive. Sanchez plays like a really good backup, and we still need to be convinced Ponder has special NFL skills. He's early in his development.
Squint and you can see a breakout for many of these quarterbacks. Most will have to be managed for their teams to win.
Tannehill has the traits of a quality long-term starter, but this year should be rough. The same is true for Weeden and his traits are less impressive. Gabbert showed progress this preseason, but that doesn't make him an above-average starter yet. Skelton and Kolb appear to be regressing under Ken Whisenhunt.
We'll revisit these rankings after the season starts, so that they look suitably foolish in retrospect.Follow Gregg Rosenthal on Twitter @greggrosenthal.