Aside from the 03 Dr. Pepper Game, 03 at Nebraska was the most entertaining game that I have ever been to.
Going back to the original two games being compared though, I was at both 01 @OU and 02 @CU and the entertainment value for the casual college football fan was probably a toss up (both were extremely entertaining). I think back to the 01 OU game and it honestly compares to 07 at Auburn in that we had a young promising QB that led us to a moral victory on national TV. (Also, College Gameday was in Norman for the 01 game) 02 at Colorado was one of the biggest KITN games that I've ever been to, and we would have been National Championship contenders that season if we had won that game. Overall, I had a much better experience at the OU game than the CU one.