According to pifeedback.com, Terminator: the Sarah Connor Chronicles had 8.84 million viewers, ranked #4 Viewers overall, and ranked #3 with viewers A18-49: 3.5/ 8

Relative to other FOX shows (with the Superbowl & American Idol taking up the 4 of the top 5 rungs), 1.4 T:tSCC ranked 13th on the network.

Tv by the numbers has released time shifted Broadcast show statistics for the weeks of Jan 7-13 and 14-20.

January 7-13
T:tSCC ranked 6th in time shift increases
Persons Live+7 (000): 19,167
Persons Live (000): 17,414 
Timeshifed Audience (000s): 1,753
% Increase Over Live: 10.1%

January 14-20
T:tSCC ranked 4th in time shift increases
Persons Live+7 (000): 10,998     
Persons Live (000): 9,182
Timeshifed Audience (000s):1,816     
% Increase Over Live:19.8%

On iTunes, 2/6/08 for tv downloads,
1.4-Heavy Metal ranks #1, 1.3-The Turk ranks 8th, 1.2-Gnothi Seauton ranks 10th.

Sources
http://pifeedback.com/eve/forums/a/tpc/f/63310451/m/772103101
http://tvbythenumbers.com/2008/01/28/top-timeshifted-broadcast-shows-january-7-13/2482
http://tvbythenumbers.com/2008/02/04/top-timeshifted-broadcast-shows-january-14-20/2556
http://www.apple.com/itunes/store/tvshows.html