WORTH NOTING ON TV

* THURSDAY

Cheers (NBC, 9:30-11 p.m.): In the mother of all sitcom finales, TV's longest-running current comedy offers its last episode - expanded to 90 minutes and attended by enough hype to make you wonder if the ending has become bigger than the show that's ending (See related story, right). Shelley Long has been brought back to reprise her Emmy-Award-winning role as Diane Chambers, and the final seven minutes of the show was filmed without a studio audience so final plot twists could be kept secret until air t ime. NBC is charging $650,000 for a 30-second spot during the final episode, and local NBC affiliates are cashing in with call-in contests and other promotional devices. In Sacramento, Calif., for instance, both a "Cheers" look-alike and a "The Sam Malone Dating Game" contest were announced, as well as a "Carla Lozupone Tortelli Le Bec" insult competition. Columbia House is selling a home video series called "Cheers: the Collector's Edition." The program airing on NBC just before the final "Cheers" is being

touted as a "pre-game" show, as if in recognition of the fact the whole occasion has become an event rather than just a drama. The same evening, the "Tonight" show will air live from the Bull & Finch Pub in Boston, the tavern that inspired the "Cheers" format.

The irony, of course, is that the literate series at the center of attention does deserves accolades. Its insight and deceptive lightness of touch are refreshing anomalies in a TV universe where success is usually gained in cruder and far less skillful strokes. But what's happening here is a bit much.

Cheers: Triumph and Tragedy (Comedy Central, 11-11:30 p.m., E.T.): This cable channel likes to capitalize on the "Cheers" brand of excess by taking such high-profile events and refracting them through its own comic prism. By holding a funny-house mirror up to inflated occasions, the channel lets viewers know when it thinks the juggernaut is out of control, and the "Cheers" finale provides perfect fodder. This spoof offers a "post-game analysis" scheduled, the channel says, "in a shameless effort to clamb er aboard the `Cheers' publicity bandwagon."