"Friends" (search) was a friend to the end for NBC, with the sitcom's final episode boosting the network to its best weekly showing in two years.

Thursday's "Friends" finale, which drew an average 52.5 million viewers, was the top-rated entertainment show on any network since the "Seinfeld" (search) finale six years ago.

"Friends" ranks as the fourth most-watched series finale in TV history, behind CBS' "M-A-S-H" (106 million), and NBC's "Cheers" (search) (80.4 million) and "Seinfeld" (76.3 million).

NBC had more to crow about, according to Nielsen Media Research figures. Besides the top-rated sitcom, NBC aired the most-watched drama series ("ER") and TV movie (part two of the earthquake drama "10.5").

That programming firepower gave NBC its best two-year showing among total viewers and matched its highest non-Olympic weekly rating in more than four years among viewers 18 to 49.

NBC's "Nightly News," however, was edged out of the No. 1 spot, averaging 8.7 million viewers (6.2 rating, 14 share), to 8.9 million viewers for "ABC World News Tonight" (6.3 rating, 13 share). "CBS Evening News" was third with 6.7 million viewers (4.9 rating, 11 share). NBC's newscast has been No. 1 for 60 of the last 63 weeks.

CBS had bragging rights in the reality realm. CBS' "Survivor All-Stars" (search) finale and reunion show each pulled in audiences of about 24 million to finish at No. 5 and 6 for the week.

NBC averaged 14.9 million viewers in prime time for the week (5.4 rating, 15 share), besting CBS' 13.2 million (4.8 rating, 13 share). NBC won handily among viewers aged 18-to-49, the demographic group it focuses on.

A ratings point represents 1,084,000 households, or 1 percent of the nation's estimated 108.4 million TV homes. The share is the percentage of in-use televisions tuned to a given show.

For the week of May 3-9, the top 10 shows, their networks and viewerships: "Friends," NBC, 52.5 million; "Friends Clipshow," NBC, 36.9 million; "ER," NBC, 28.4 million; "Survivor All-Stars Finale," CBS, 24.8 million; "Survivor All-Stars Reunion," CBS, 23.9 million; "American Idol" (Tuesday), Fox, 22.8 million; "American Idol" (Wednesday) Fox, 21.2 million; "CSI," CBS, 20.4 million viewers; "NBC Movie of the Week: '10.5'" (Monday) NBC, 19.9 million; "Survivor: All-Stars," CBS, 19.2 million.