Colorado fan here. But never one to not like a team like the Cougs. Some in this thread may be giving a little too much credit to CU's defense, and not quite enough to their offense. The Buffs are a balanced team.
CU's weakness, and it's a critical one, is just awful field goal kicking (two season-long injuries screwed it up.) There're also a couple of other questions -- is the QB, Sefo Liufau hiding an ankle injury that makes for erratic passing (and potential interceptions)? And, are injuries to their offensive line going to take a toll in the running game and QB protection?
CU's strength comes from a couple of areas, the most important is that they are the most experienced team in the conference. On top of that, the two coaches who have been added to the program, DC Jim Leavitt (former 49'ers assistant and USF head coach) and Darrin Chiaverini (NFL'er and Texas Tech assistant) have masterly changed the internal dynamics.
I expect a good game, an exciting one. With a good team, Folsom Field can be one of the hardest places to play away at anywhere. And this year, finally after the long painful dark ages, the Buffs once again are a good team.