THURSDAY Prime Time Live (ABC, 10-11 p.m., ET): Premi`ere of a weekly show whose format, for some reason, they're carefully not calling a ``magazine.'' But consider a few of the categories to be included in the months ahead: investigative reports, celebrity profiles, feature stories, and lots more. There'll even be some back-and-forth with a studio audience - all of this anchored by Diane Sawyer and Sam Donaldson, who will do a lot of traveling for their reports. SUNDAY Football in London? (NBC, 1-4 p.m.): Yes, London - it's the third year, in fact, a pre-season NFL game is being played there, as part of an effort to capitalize on an apparently growing interest by the British in this ``All-American'' sport. Covered live from Wembley Stadium, the contest is between the Cleveland Browns and the Philadelphia eagles. MONDAY Ralph McGill and the Segregated South (PBS, 10-11 p.m.): ``Dawn's Early Light'' portrays the outspoken anti-segregationist Southerner whose front-page column appeared in the Atlanta Constitution (please see preview in this section appearing on Aug. 4). TUESDAY P.O.V. (PBS, 10-11 p.m.): ``Point of View'' - a series of independent films - takes an investigative look at the effects on people of nuclear energy plants in ``Dark Circle''- (watch for review in the Aug. 7 Arts section). Please check local listings for all programs, especially on PBS.