Big Brother RatingsThursday night’s primetime brought a debut, a finale and another chance for Americans to vote. On CBS’ live 9 PM Big Brother (2.2/7), host Julie Chen announced a new “America’s Vote” where viewers can decide whether the show’s coaches can jump into the contest. The twist didn’t add much as the reality show was flat with last week’s Thursday broadcast. The network followed with the premiere of the dating show 3 (0.8/2): It was the lowest rating CBS has ever had with a new series. On Fox, Take Me Out (1.2/4) wrapped its first season; the George Lopez-hosted dating show was flat with last week. ABC had a new two-hour episode of Wipeout (2.2/7), up 27% from last week’s show to a summer high. The network followed with a new Rookie Blue (1.5/5), which rose 7% from its July 19 broadcast. The pair helped ABC win the night in adults 18-49 and total viewers with 6.4 million.

On the day before it begins wall-to-wall Olympics coverage, NBC had a new Saving Hope (0.6/2), which was up 20% from last week, and a new Rock Center With Brian Williams (0.8/2), which was up 14% from its July 19 show. Earlier, CBS ran repeats of The Big Bang Theory (2.2/8) at 8 PM and Two And A Half Men (2.0/7) at 8:30. NBC had encore broadcasts of The Office (0.7/2) and Parks And Recreation (0.6/2) on in the same time slots. Fox had a Glee (0.6/2) repeat at 9 PM.

Deadline's Dominic Patten - tip him here.