Fast National ratings for Thursday, May 17, 2012.
FOX won Thursday night among young viewers as "American Idol" got a solid bump for the season's penultimate results show, while the finales of "Person of Interest" and "The Mentalist" carried CBS to a slim overall victory.
Meanwhile, ABC's "Grey's Anatomy" got a big boost for its heavily promoted finale and helped lift "Scandal" to a big finale as well. And NBC's strategy 90 minutes of "Community" yielded better-than-"Awake" numbers, which was probably all the network was hoping for when it swapped shows in the 9 p.m. hour.
Among adults 18-49, FOX won Thursday night with a 3.0 rating, tops in the key demographic. ABC averaged a 2.5 rating for second, while CBS' 2.4 rating was close behind in third. There was then a big drop to NBC's 1.1 key demo rating and The CW's 0.3 key demo rating.
Overall, though, CBS averaged an estimated 11.37 million viewers and a 7.1 rating/12 share, edging out FOX's 6.8/11 and 11.09 million viewers. ABC was  third with 5.6/9 and 8.39 million viewers. After another huge drop, NBC averaged 2.53 million viewers and a 1.6/3. The CW's 838,000 viewers and 0.6/1 trailed for the night.
[Univision averaged 3.72 million viewers and a 1.5 rating among adults 18-49 for Thursday evening.]
8 p.m. - FOX's "American Idol" started primetime in first with 15.85 million viewers and a 4.2 rating among adults 18-49 for "American Idol." CBS was a distant second with a repeat of "Big Bang Theory" (8.3 million and a 2.4 key demo) and a new "Rules of Engagement" (7.28 million and a 2.1 key demo). ABC's series finale of "Missing" rose a bit with 6.485 million viewers and a 1.3 key demo rating. NBC was fourth with "Community" (2.99 million and a 1.3 key demo) and the "30 Rock" finale (2.85 million and a 1.3 key demo). The CW aired something linked to Perez Hilton and averaged 965,000 viewers and a 0.3 key demo rating.
9 p.m. - The "Person of Interest" finale grabbed first overall for the 9 p.m. hour with 13.35 million viewers, but CBS finished a distant second among adults 18-49 with a 2.5 rating. ABC's "Grey's Anatomy" had a big night with 11.15 million viewers and a 3.9 key demo rating for its finale. FOX's "Touch" slipped to 6.34 million viewers and a 1.8 key demo rating against the touch competition. NBC's two season-closing episodes of "Community" averaged 2.55 million viewers and a 1.3 key demo rating. A repeat of "The Vampire Diaries" averaged 711,000 viewers and a 0.2 key demo rating on The CW.
10 p.m. - CBS' season finale of "The Mentalist" averaged 12.96 million viewers and a 2.5 rating among adults 18-49 to win the 10 p.m. hour. ABC's "Scandal" finale was second with 7.52 million viewers and a 2.4 key demo rating. On NBC, "Awake" averaged 2.11 million viewers and a 0.7 key demo rating.

All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.
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.