The ratings are in from Saturday night's head-to-head MMA events and the UFC wins although Strikeforce put in a very respectable showing. 

Dave Meltzer reports on the Wrestling Observer (subscription required and worth every penny):

1.4 for the TUF finale

The Strikeforce show did a 1.2, although given the different sized univeses, that's 2 million viewers to 341,000

Sergio Non has more:

In mixed martial arts' core demographics of men ages 18-to-34 and 18-to-49, the TUF finale saw 2.3 and 1.9 ratings, compared to 0.81 and 0.9 for Strikeforce, Spike said.

As part of many basic packages offered by cable and satellite TV providers, Spike is available in more than 98 million homes. Showtime, a premium channel that costs an additional fee, has about 18 million subscribers.
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TUF's show peaked at 2.3 million viewers between 10:15 p.m. and 10:30 p.m., when Nam Phan and Leonard Garcia went three rounds in bout packed with enough action to win Fight of the Night for the broadcast. Garcia was awarded a heavily disputed split decision.

MMA Junkie has more on the Strikeforce numbers:

This past weekend's "Strikeforce Henderson vs. Babalu II" event on Showtime peaked with 465,000 viewers for a main event between Dan Henderson and Renato "Babalu" Sobral.
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The numbers were similar to October's "Strikeforce: Diaz vs. Noons 2" event in San Jose, which averaged 350,000 viewers and peaked with 509,000. However, of the organization's seven "Arena Series" shows in 2010, the Dec. 4 event ranked fifth (but just 26,000 viewers behind the third-ranked "Strikeforce: Houston" card).