this is from an article back in November, which shows the challenge they will face with CBS:
MMA insiders believe CBS is looking at a Saturday night prime-time slot. CBS averaged a 4.5 rating in prime time on Nov. 24, a number no UFC event has approached. However, major UFC events such as Ken Shamrock vs. Tito Ortiz in 2006 and this year's Dan Henderson vs. Quinton Jackson Pride vs. UFC title unification match have beaten all network programming in the highly sought 18-34 male demographic despite airing on basic cable's Spike TV.
The Henderson-Jackson fight did a 5.7 in that demo. In males 18-49, it beat everything on both cable and network for the day, including a slew of major college football games. The right fight with the right hype could be a strong vehicle for advertisers to target young males, which CBS, an older-skewing network, is looking to capture.
The highest rating a UFC event has ever drawn is a 3.1, for both the aforementioned shows. Otherwise, the highest-rated Ultimate Fighter finals on Spike have done 2.0 ratings. That's a big success for Spike, but it would be a failure on CBS.
So I'm not sure how many times they will be on CBS, but they just need to make sure to promote it correctly, and be smart about who fights.