WORTH NOTING ON TV

* FRIDAY

Earlyprime (CNN, 5-5:30 p.m.): This news-and-information program - designed for baby boomers and what it calls "the mature audience" - is offering a special called "Coming of Age: Golden Adventures." It suggests there can be more to holidays for seniors than getting off tour buses, saying "Oh, yes" as they take in the sights, and climbing back on the buses. There is, in fact, a growing interest among seniors in trips that challenge them physically and help them learn something. The show joins a mountain hike in Glacier National Park, a Salmon River whitewater camping trip, a wagon train through the South Dakota hills, and other ventures. The host is "Earlyprime" co-anchor Natalie Allen.

Evening News From Moscow (C-Span, 6-6:30 p.m.): The regular broadcast from Russia. * MONDAY

Late Show With David Letterman (CBS, 11:35 p.m.-12:35 a.m., E.T.): The promotion is over, the maneuvering done, and it's time to deliver. David Letterman must now show us that his jaunty appeal can remain intact in the somewhat less free-wheeling format of the not-so-late-night time slot. His impressive guest list for the first week includes Robin Williams, Martin Short, John Mellencamp, Debra Winger, and other actors, comedians, and musicians.

In a bow to nostalgia, one guest on the opening night is Bill Murray, who was the first to appear on Letterman's show when it opened on NBC Feb. 1, 1982. (That 11-year-old visit by Murray will, curiously, be re-airing later the same night as one of the final broadcasts of NBC'S "Late Night With David Letterman.") Another guest for the new show is Billy Joel, whose recently released CD, "River of Dreams," may be one reason for his appearance.

Paul Shaffer and the CBS Orchestra will be on hand for the debut. Lately of Letterman's NBC show, Shaffer will lead a bigger band.

Please check local listings for these programs.