This Saturday in Las Vegas, UFC 94 will feature one of the most highly anticipated Mixed Martial Arts fights in history - Georges St. Pierre vs. BJ Penn. Both fighters are in their prime, the champions of their respective divisions, and are two of the most dynamic fighters in mixed martial arts today.
Georges St. Pierre - Welterweight Champion

BJ Penn - Lightweight Champion

The History
With all the hype surrounding their upcoming fight, you would think that St. Pierre and Penn have never fought before. St. Pierre and Penn, however, have indeed fought in the past and met 3 years ago in a closely contested fight that saw St. Pierre take home a victory in a close split-decision.
In their previous fight, Penn came out strong and dominated St. Pierre in the first round with his world class striking, landing some effective shots with pinpoint accuracy. In the later two rounds, however, St. Pierre rallied back and relied on a series of takedowns to eek out a decision victory.
The Fight
A lot has changed since Penn and St. Pierre first fought, and it can be argued that both fighters have changed enough to make their previous fight irrelevant in analyzing their upcoming fight.
As stated earlier, one of Penn's biggest faults earlier in his career was his proper lack of conditioning. Penn's cardio even caused him to lose an important match up to Matt Hughes a few years back when he gassed out and Hughes was able to take advantage of Penn, who had been winning the fight up until that point.
This, though, is the biggest fight of Penn's career, and contrary to what ever image they tried to portray on UFC Primetime, you better believe that Penn is taking this fight seriously and is going to step into the octagon in great fighting shape.
When it comes to St. Pierre, it's hard to find any weakness's in his game. He's constantly improving, is unbelievably strong for his weight class, is super quick, and is nearly impossible to take down. Some, however, have questioned his chin, and it will be interesting to see how St. Pierre will be able to fare against Penn's world class striking.
What makes this fight so exciting is that both fighters are at the top of their game, and they both want to win this one BAD. There's even been some trash talk between the two (mostly from Penn) as the night of the fight draws near. Penn has called St. Pierre a 'quitter' and a 'little bitch', and has even had some not-so-nice remarks about St. Pierre's head trainer. St. Pierre, who isn't much of a trash talker, simply countered and said that Penn is talking trash because that's the only way he can build up his confidence for the fight.
It's important to point out the weight difference between the two fighters as BJ Penn is moving up a weight class to fight St. Pierre. Penn will most likely enter the octagon weighing in at around 170 lbs. St. Pierre, meanwhile, will weigh in at 170 lbs, but will most likely enter the octagon at around 185 lbs. 15 pounds is a significant weight advantage, but BJ Penn used to be the Welterweight champion, so that shouldn't be much of an issue. Also, keep in mind that Penn even fought once at 205 pounds (and lost to Lyoto Machida belive it or not).
With all that said, this fight will come down to pure skill and heart, and overall, I have to give this fight to St. Pierre. St. Pierre is just too dangerous in too many different ways. He's constantly evolving and Penn might have a hard time dealing with St. Pierre's strength advantage. Also, the level of competition St. Pierre has faced over the past year is a notch ahead of what Penn has faced.
A motivated and in shape BJ Penn is a scary thought, but St. Pierre is a world class mma fighter who hasn't even peaked yet. He's survived strikes from Penn before, and is strong enough and skilled enough to avoid any of BJ's submissions on the ground. Overall, I have to give the edge to St. Pierre by a hair.