Fast National ratings for Thursday, May 13, 2010.
 
ABC won two-thirds of Thursday night in the key demographic, but thanks to another dismal performance by "FlashForward," CBS was still able to eke out a win for the night in the demo, while dominating overall.
 
Among adults 18-49, CBS averaged a 3.3 rating, beating the 2.8 rating for ABC in the all-important age group. FOX's 2.4 rating and the 2.2 rating for NBC followed. The CW's solid 1.5 rating was fifth.
 
Overall, CBS had a larger margin of victory, averaging an estimated 13.61 million viewers to go with an 8.3 rating/14 share. ABC's 5.6/9 was second, with FOX taking third with a 4.6/8. NBC's 2.9/5 held off the 2.0/3 for The CW.
 
CBS won the 8 p.m. hour with a 7.6/13 and a 3.9 demo rating for "Survivor: Heroes vs. Villains." FOX's "Bones" was a sturdy second with a 5.6/10, slightly up from last week. ABC's "FlashForward" was third overall with a 3.2/6, but dead last in the demo with a 1.3 rating. NBC's "Community" and "Parks and Recreation" had a 2.7/5 for the hour, as the addition of Rob Lowe to the "P&R" cast produced a statistically irrelevant bump in the 18-49 demo and a statistically irrelevant drop in total viewers. The CW's "The Vampire Diaries" closed its first season with a 2.1/4 and a 1.7 demo rating.
 
"CSI: Crime Scene Investigation" kept CBS in first overall at 9 p.m. with an 8.1/13, though CBS was third in the demo. ABC's "Grey's Anatomy" was second overall with a 7.2/12, but first in the demo with a 3.8 rating. FOX's had a 3.7/6 and a 2.3 demo rating. NBC finished fourth overall with a 3.5/6 for "The Office" and "30 Rock," but came in second in the demo. The CW's "Supernatural" got a small bump for its season finale.
 
"The Mentalist" completed CBS' overall sweep with a 9.1/16. ABC's "Private Practice" got a finale bump and did a 6.3/11 overall and a 3.2 demo rating, taking first for the hour. NBC's "The Marriage Ref" was substantially down from last week in a distant 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.
Dan-feinberg-med
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.