Who Else Has Left Grey's Anatomy?

Hit series losing grip on TV's demographically desirable, letting The Office back in the game

Why is Katherine Heigl not alone? Is David Letterman beating Jay Leno yet? And who's the new boss of Sunday night? (Hint: It's not Donald Trump.)

The answers—and more questions about Lady Gaga, Pretty Wild, The Bachelor and more—in the latest TV ratings quiz:

1. After Heigl, who else is leaving Grey's Anatomy? The demographically desirable. For the last two weeks, The Office has either tied Grey's or outright won the shows' head-to-head battle for all-important young adults. That just doesn't happen. (Until it happened.)

2. What's the overall condition of the patient? Good. Grey's remains TV's hippest scripted hit, next to The Big Bang Theory and just behind Lost.

3. Letterman or Leno? Leno. Letterman's Late Show snuck in a nightly win there last Tuesday, but other than that blip, it's been all Tonight Show.

4. If the answer's not Celebrity Apprentice or, more surprisingly, Desperate Housewives, who's ruling Sunday night? Undercover Boss. The upstart's actually ruling all of TV as its most-watched reality series—even outnumbering Survivor.

5. How much is a Lady Gaga "Telephone" call worth? Viewership for the 11:30 p.m. Thursday edition of E! News, featuring the pop star's music-video premiere, spiked by one-third. 

6. What's hotter: old stuff or new Project Runways? The relic-hunting American Pickers outdrew every reality series on cable, save the likewise used world of Pawn Stars, per the latest weekly Nielsen rankings. Other standouts: the season finale of Hannah Montana, which was cable's all-around No. 1 show; Sonny With a Chance; and White Collar. 

7. Complete the following sentence: A TV critic warned Pretty Wild would bring Western civilization "a little closer to its final collapse," so audiences _____. "Made sure to tune in, baby!" The E! series got off to a solid start Sunday (1.7 million viewers), boosted by big numbers for the second-season premiere of Kendra (2.5 million).

8. What will prevent TV critics from hurling themselves from great heights? The fact that their acclaimed WWII miniseries The Pacific got off to an even bigger start on Sunday, scoring 3.1 million pay-cable viewers in the HBO show's premiere.

9. How did ABC's attempt to milk The Bachelor for one more week go? Not bad, estimates show. Last night's very special 20/20 report on the franchise scored nearly 8 million completists, opposite CBS' comedies House and 24.

Here's a look at the top 10 broadcast network shows for the week ended Sunday, per Nielsen Media Research:

1. American Idol (Tuesday), 22.8 million
2. American Idol (Wednesday), 20.7 million
3. NCIS, 19.6 million
4. American Idol (Thursday), 19.3 million
5. Two and a Half Men, 17.6 million
6. NCIS: Los Angeles, 17 million
7. The Big Bang Theory, 16.3 million
8. The Mentalist, 16 million
9. CSI, 15.2 million
10. The Good Wife, 14 million