NBC Renews: ‘Biggest Loser,’ ‘Sing-Off,’ ‘Who Do You Think You Are?’

Making its first moves under new entertainment chief Bob Greenblatt, network re-ups its alternative slate for 2011-12

Making its first big programming moves under new entertainment chief Bob Greenblatt, NBC announced Tuesday the renewal of most of its alternative series slate, re-upping "The Biggest Loser," "Who Do You Think You Are?" and "The Sing-Off" for 2011-12.

"Alternative series such as these three bona fide hits are important not only to their loyal audiences but also as strong components of the NBC schedule," said Greenblatt in a statement. “They are each unique, attention-getting shows with terrific producing and talent auspices, and we're proud to be associated with them."

"The Biggest Loser 10" averaged a 3.1 rating/8 share in adults 18-49 and 8.3 million viewers overall in the fall and "The Biggest Loser 11" is averaging a 3.3/9 in 18-49 and 9 million viewers overall so far this winter. "The Biggest Loser" is NBC's No. 1 entertainment series among women 18-49 and women 25-54.

This season's cycle of "The Sing-Off" averaged a 3.2/8 in adults 18-49 and 9.2 viewers overall, up 28 percent in 18-49 rating and 27 percent in total viewers over last season

Season two of the Lisa Kudrow-produced "Who Do You Think You Are?" is averaging a 1.4/5 in adults 18-49 and 7 million viewers overall over its first two weeks, making it NBC's top Friday series so far this season in total viewers.