Wednesday Primetime Results:

· From 8-10 p.m. ET, "The Sing-Off" (1.6/5 in 18-49, 5.4 million viewers overall) tied for #1 in the time period in adults 18-49 among ABC, CBS, NBC and Fox. It's the first time this season NBC has won a share of the time-period lead among the Big 4 nets in the Wednesday 8-10 p.m. slot in 18-49.

· In the time period, "The Sing-Off" also ranked #1 outright among those nets in women 18-49 and adults, men and women 18-34. Head to head versus Fox's "X Factor," "The Sing-Off" prevailed in 18-49 (1.6 vs. 1.3) and total viewers (5.4 million vs. 5.0 million).

· From 10-11 p.m. ET, "Michael Bublé's 3rd Annual Christmas Special" (1.3/4 in adults 18-49, 5.0 million viewers overall) ranked #2 in its slot among ABC, CBS and NBC in adults 18-49, women 18-49 and adults, men and women 18-34.

In Late-Night Metered Markets Wednesday night:

· In Nielsen's 56 metered markets, household results were: "The Tonight Show with Jay Leno," 2.9/8; CBS's "Late Show with David Letterman," 2.3/6; and ABC's "Jimmy Kimmel Live," 2.4/6.

· In the 25 markets with Local People Meters, adult 18-49 results were: "The Tonight Show with Jay Leno," 0.9/5; "Late Show," 0.5/3; and "Jimmy Kimmel Live," 0.8/4.

· From 12:35-1:05 a.m. ET, ABC's "Nightline" averaged a 1.5/5 in metered-market households and a 0.5/3 in 18-49 in the Local People Meters.

· From 12:35-1:35 a.m. ET, "Late Night with Jimmy Fallon" (1.4/5 in metered-market households with an encore telecast) beat CBS's first-run "Late Late Show with Craig Ferguson" (1.2/4). In the 25 markets with Local People Meters, "Late Night" (0.5/4 in 18-49 with an encore) topped "Late Late Show" (0.3/2).

· At 1:35 a.m., "Last Call with Carson Daly" averaged a 0.7/3 in metered-market households with an encore and a 0.3/3 in adults 18-49 in the 25 markets with local people meters.

NOTE: All ratings are "live plus same day" from Nielsen Media Research unless otherwise indicated.