UFC 129. For some reason I bought into the hype that Shields-GSP would be intersting. But, this was also the event in the Skydome, with like 60k spectators. And there were 2 title fights, the other one with Aldo, who seemed like a total wrecking machine at one time. Plus, Machida-Couture.
It would have been one of the best events ever if the main event hadnt been such a shitfest.