Fast National ratings for Thursday, March 25, 2010.
Coverage of the NCAA Tournament's Sweet 16 games pushed CBS to a comfortable win on Thursday night.
In other notable ratings news, The CW's "The Vampire Diaries" had a soft return after a long hiatus, while ABC's "FlashForward" continued to slip in its second week back.
Among adults 18-49, CBS averaged a 3.8 rating, topping the 2.8 rating for ABC and NBC's 2.6 rating. The CW was fourth in the all-important demographic with a 1.4 rating, beating the 1.3 rating for FOX. 
Overall, CBS averaged an estimated 11.078 million viewers to go with a 6.9 rating/12 share. ABC's 5.8/10 was a solid second. NBC finished third with a 3.8/6, with FOX's 3.2/5 close behind. The CW trailed with a 1.8/3.
CBS' basketball coverage began the night in first with a 6.7/11 and a 3.6 demo rating. ABC's "Flashforward" was second overall with a 4.1/7 and a 1.8 rating in the demo, both slightly down from last week. FOX's "Bones" repeat beat the 3.1/5 for NBC's "Community" and "Parks and Recreation," though the comedies were second for the hour in the demo. The return of "Vampire Diaries" had a 1.9/3 for The CW, averaging 3.24 million viewers and a 1.5 demo rating.
ABC's "Grey's Anatomy" did a 7.5/12 in the 9 p.m. hour, beating the 7.4/12 for CBS' basketball, but CBS averaged more viewers and a higher 18-49 demo rating. NBC's "The Office" and "30 Rock" averaged a 4.1/7 for third. FOX's "Fringe" repeat beat the 1.7/3 for "Supernatural" overall, but The CW's drama topped FOX in the demo.
CBS was back in first at 10 p.m. with a 6.6/11 and a 3.9 demo rating for NCAA basketball. ABC's "Private Practice" was second with a 5.9/10. That left NBC's "The Marriage Ref" in third. 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change, particularly in the case of live events.
A long-time member of the TCA Board and a longer-time blogger of "American Idol," Dan Fienberg writes about TV, except for when he writes about movies or sometimes writes about the Red Sox. But never music. He would sound stupid talking about music.