Christina Applegate, Will Arnett

Amid beginnings and endings among reality shows, America's Got Talent — the summer's most popular show — entertained 14 million viewers as it crowned its latest champ, providing a big lead-in for two new sitcoms ... with mixed results.

The Winner of America's Got Talent Is ...

Preliminary Nielsen figures also showed that that the two-hour NBC talent show snared a 3.6 rating among 18-to-49-year-olds, down some 10 percent from last year's finale.

And the Big Brother winner is ...

Big Brother — which had its best ratings in seven years and has already been renewed for a 14th edition next summer — also picked a winner as 7.78 million tuned in for its 90-minute season-ender. Its 2.9 demo rating stayed even with last year's conclusion.

It was preceded on CBS by the 90-minute Survivor: South Pacific debut, which lured 10.57 million people and a 3.4 demo rating — a decrease of some 15 percent vs. a year earlier, making it the show's worst autumn start of all time. It was up 6 percent from the spring debut, though.

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After Talent, Up All Night  at 10/9c debuted to 10.91 million viewers and posted the night's high 3.7 demo rating. At 10:30/9:30c, Free Agents signed up 6.34 million and a 2.1 rating. In the time slot occupied last year by the execrable Outlaw, Night's demo marked a 54 percent improvement over that show's first half-hour — but Agents' demo was the same as Outlaw's in the last half-hour. Both sitcoms will move to their regular time slots next Wednesday in the 8 o'clock hour.

Besides the last hour of Big Brother, the new shows competed with ABC News' prime-time edition of Nightline about the modeling industry, which grabbed 4.13 million.

Fall TV Popularity Contest: Are you a H8R hater? Love Up All Night, Free Agents?

On The CW, 1.3 million people sampled the premiere of H8R (0.6 demo rating), and 1.91 million viewers cat-walked to the 17th edition (with an all-star cast) of America's Next Top Model (0.9).

Fox went with a fresh Buried Treasure installment, then a rerun of the show, pulling 2.78 million and 3.05 million, respectively.