There really are no weaknesses in relation to other fighters. That said, Matt Serra once proved he's not unbeatable. In other words, if you tag him, he can be taken out.
What Carlos Condit (27-5) brings to the table: Condit is a complete MMA fighter. We're talking about a guy that brings an even amount of submission (13) and (T)KO victories (13) into this encounter. He's technically sound on his feet, has solid wrestling skills, and is a well above average Brazilian Jiu Jitsu practitioner. He's capable of causing guys to tap from both the top and bottom position. What's more, Condit has shown a lot of power recently, having (T)KO'd Rory MacDonald, Dan Hardy, and Dong Hyun Kim consecutively.
The weaknesses? Well, he's a solid wrestler; but Condit can be taken down. And that's about it.
Georges St. Pierre vs. Carlos Condit Prediction: On their feet, this one is close. I like St. Pierre's athleticism a little bit more, but things could go either way there. However, guess is that if St. Pierre wants to put his UFC 137 opponent on the canvas, he can. And that's significant, as it offers St. Pierre a couple of options. In the end, I expect the Canadian champion to strike a little bit before taking this fight to the canvas. Once there, expect him to pound on Condit for several rounds. It won't be easy, as Condit is dangerous off of his back. Then again, the man they call "Rush" has dealt with BJ Penn off of his back, so he's very capable there.
Georges St. Pierre defeats Carlos Condit by decision.