Here are a few select thoughts.
Sok: Very talented but overhyped (remember Rogan going off!). He was simply outskilled. I'm not sure how much was Octagon jitters and how much was him drowning in the hype about his invincibility but he looked helpless on the ground. Where was the hip movement? The first thing they teach you in naiwaza in Judo is the "ebi." More fight time in the Octagon and a loss like this is exactly what this 23 y/o needs in his early career to improve. His next fight should be very revealing.
Wandy: As a big fan of his, I was disappointed. Sure, he's tough but what a shitty, one-dimentional gameplan. This was a boxing match and he lost to a more skilled boxer. Speculating about the role of steroids is truly just that: "speculation." He definitely had the Octagon jitters. All that being said, it may have been a completely different game with Pride rules and Chuck slipped a few times and was prone to some crazy soccer kicks. Rampage of today would beat Wandy of last night in the Octagon.
GSP: Never have I been so impressed with the raw skill of an MMA fighter as I was last night. It takes some talent to make Matt Hughes look so helpless and inferior in every position. He was fluid and mixed it up well standing and on the ground. Now I realize that his previous loss was "the best thing" for him because he is more motivated and focused than ever. This was a symbolic passing of the torch to the new generation of MMA champions. Being a strong wrestler with a bit of submission and mediocre boxing will no longer be enough in this sport.
I couldn't even go talk to Matt Serra (he was a few rows from me at his Madison Sq Garden viewing party) after this match, realizing that he would soon be eaten alive by the hungry Canadian.