Rankings are often a heated topic in mixed martial arts circles. They're so very subjective; your rankings likely look entirely different than mine, and the fan sitting next to you at the bar likely has a very different opinion on the subject.
Rankings are also useless. As we've recently seen in the UFC, rankings are a mythical creature that have zero effect on title shots or perceived standing in each weight class. If they had any weight at all, we wouldn't have seen Vitor Belfort face Jon Jones, we wouldn't see Jones defending his belt against Chael Sonnen, and Nick Diaz would need to win at least one fight before facing off with Georges St-Pierre.
But even though they're useless, rankings are also fun, and nothing is more fun (or useless) than pound-for-pound rankings.
With that in mind, here are my pound-for-pound MMA rankings for December 2012.
The reigning UFC middleweight champion has been on top of everyone's pound-for-pound lists for what feels like an eternity.
In reality, Anderson Silva has dominated the sport for just over six years; but in the ever-changing world of mixed martial arts, that might as well be 25 years. And Silva hasn't just dominated at middleweight; he's also tried his hand at light heavyweight on three different occasions, and somehow looked even more dominant than he does in his natural weight class.
Make no mistake about it: Until Silva suddenly gets old and loses a fight, this spot is his.
WHAT'S NEXT: With the dream fight against Georges St-Pierre scuttled, Silva will likely face a middleweight contender at some point in 2013. Michael Bisping remains the top possibility, as long as he gets past Vitor Belfort at UFC on FX 7 in January. After that, a jaunt to light heavyweight for a superfight against Jon Jones remains a possibility.
Jon Jones has established himself as one of the greatest light heavyweights of all time. Should Jones beat Chael Sonnen in April, he'll tie Tito Ortiz's record for the most consecutive UFC light heavyweight title defenses, and Jones should own the record on his own by the end of 2013.
After that? He'll probably move to heavyweight, and we'll get to see all kinds of interesting fights. Jones vs. Junior Dos Santos, Cain Velasquez and Alistair Overeem all remain possibilities over the next few years, and the phenom still has plenty of years left in the sport.
It's a good time to be a fight fan.
WHAT'S NEXT: Jones faces Chael Sonnen at a UFC pay-per-view on April 27.
Georges St-Pierre returned from a long layoff to dominate Carlos Condit for nearly five full rounds, re-establishing himself as the king of the welterweight division.
A superfight with Anderson Silva seems like a pipe dream at this point, but St-Pierre has plenty of interesting challengers remaining in his own division. Johny Hendricks is the top contender, but he's been bypassed in favor of a big-money fight with Nick Diaz.
St-Pierre is still in his athletic prime and looks to have years worth of top-flight action left in him.
WHAT'S NEXT: St-Pierre faces Nick Diaz at UFC 158 in March.
Jose Aldo has been on the shelf since January due to an injury suffered in a motorcycle accident this summer.
But Aldo will return on Super Bowl weekend to face Frankie Edgar in what should truly be classified as a superfight. Should Aldo win, there's a decent possibility that we'll see him move up to lightweight; the featherweight champion has expressed interest in a run at 155, and he'll have effectively cleaned out the top of his division if he gets past Edgar.
Aldo vs. Benson Henderson? Yeah, I'd watch that.
WHAT'S NEXT: Aldo faces Frankie Edgar at UFC 156 in February.
Plenty of people thought Benson Henderson didn't actually beat Frankie Edgar in his last title defense, and still others believed Edgar won the first fight.
But after Henderson's five-round shellacking of Nate Diaz, there's no question that Henderson is the ruler of the lightweight division. He beat Diaz in every area of the game and did it with confidence and style. The fans may not have perceived Henderson as a dominant lightweight before UFC on Fox 5, but it's very likely that he changed a lot of minds.
WHAT'S NEXT: Henderson likely faces Gilbert Melendez or the winner of Donald Cerrone vs. Anthony Pettis.
Frankie Edgar's run at lightweight ended with plenty of controversy and two consecutive title fight losses to Benson Henderson.
But it's that same controversy that allowed Edgar to drop to featherweight and immediately secure a title shot against Jose Aldo. And it's his excellent performances against bigger fighters at featherweight that keeps him ranked on these pound-for-pound lists. Despite the two consecutive losses, Edgar remains one of the best fighters in the world.
WHAT'S NEXT: Edgar faces Jose Aldo at UFC 156 in February
Junior Dos Santos, the reigning UFC heavyweight champion has been inactive since May, when he handily beat replacement opponent Frank Mir to defend the heavyweight title he won just over a year ago.
Dos Santos will return later this month to face Cain Velasquez, the man he beat to capture the strap in the first place, in the main event of UFC 155. It seems likely that Dos Santos will then face Alistair Overeem; the two have taken pot shots at each other through the media for months.
Overeem has to get by Antonio Silva before securing the title shot he lost when he was suspended for a drug failure, but if he does—and he's a heavy favorite to do so—we should finally see Dos Santos and Overeem settle their quibbles in the cage.
WHAT'S NEXT: Dos Santos faces Cain Velasquez at UFC 155 later this month
Dan Henderson hasn't had much luck lately. He secured a title shot against Jon Jones by defeating Mauricio Rua in an all-time classic last November, but a knee injury prevented him from facing Jones at UFC 151, ultimately leading to the cancellation of that event.
Henderson's late notice of the injury to the UFC likely led to the title shot being taken away from him, and he'll have to face Lyoto Machida at UFC 157. That's assuming, of course, that his knee is healing properly. Dana White said that Henderson may not be ready for UFC 157, which pushes back his eventual return and title shot even further down the road.
WHAT'S NEXT: Henderson faces Lyoto Machida at UFC 157
By any measure, Demetrious Johnson has been one of the best lighter-weight fighters of the past few years. Fighting against bigger men at bantamweight, Johnson lost just twice, to Brad Pickett and divisional champion Dominick Cruz.
After moving down to flyweight, he quickly established himself as the best in the world by beating Ian McCall and Joseph Benavidez, becoming the UFC's first flyweight champion in the process.
WHAT'S NEXT: Johnson faces John Dodson at UFC on Fox 6 in January
Gilbert Melendez remains the best lightweight in the world not currently signed to a UFC contract, but it appears that will change in the next few months. Strikeforce will likely run its final event in January, and Melendez isn't participating due to a shoulder injury, which means his next fight will almost assuredly be in the UFC.
We don't know if Melendez will get an immediate title shot upon entry to the UFC or if he'll need to beat an opponent before facing the UFC champion. But what we do know is that Melendez is deserving of better competition, and it looks like we'll finally get his chance.
WHAT'S NEXT: Melendez moves to the UFC and may face Benson Henderson
Jeremy Botter is a Lead Writer. Unless otherwise noted, all quotes were obtained firsthand.