The highest-rated Academy Award telecast in 10 years has given ABC the boost it needed to break a string of 17 consecutive second-place weeklong finishes and win the March 29-April 4 prime time Nielsens — ABC’s first victory since Nov. 30-Dec. 6, 1992.CBS ran a distant second last week, but it’s a measure of the Eye Network’s emerging dominance in the household ratings race that CBS has now lost just two of the last 17 weeks and both times it took colossal events on the competing webs to do it – Super Bowl week, won by NBC, and Oscar week, won by ABC. Despite CBS’ growing household strength, ABC has still won the adults 18-49 race for 18 out of 28 weeks this season. That demographic more closely reflects which net is attracting the audiences most useful to advertisers. Last week’s adults 18-49 averages were: ABC, an 8.8 rating, 23 share; CBS, 6. 6/17; NBC, 6.1/16; Fox Broadcasting Co., 5.1/14. CBS has taken the first step toward winning the current week by dominating Monday, April 5, with the NCAA college-basketball championship game. The North Carolina-Michigan showdown shot a 22.2/34 to finish 2% off of last year’s Duke-Michigan finale (22.7/35). Still, it’s the second-highest rated champ game in the last six years, dating back to the 23.1/33 of 1987′s Indiana-Syracuse contest. CBS estimates 50 million viewers watched at least some of the North Carolina-Michigan game at home and roughly another 5 million in out-of-home locations. NBC finished a competitive second for the night with the concluding episode of “Diana: Her True Story” (15.6/24). “Diana’s” two-night average is a 15.1/23, tied for fifth among the 10 multiparters aired this season. The March 29-April 4 week went to ABC, but CBS finished the period with its usual Sunday households win, albeit its least impressive in a long time. It took Moses to do it, but CBS’ string of 68 consecutive first-place half-hours over 8 1/2 Sundays was finally broken last weekend when “The Ten Commandments” led the four 9-11 p.m. half-hours. Before that, CBS had not lost a Sunday half-hour since the evening of the Super Bowl. CBS, in fact, plunged to third for the 9-11 p.m. period Sunday, behind “Commandments” and NBC’s first half of “Diana” (NBC’s top Sunday film since “Deadly Matrimony, Part 1″ last Nov. 22). The CBS vidpic “A Place To Be Loved” ended up a full 4 rating points below the lowest-rated CBS Sunday film for the span of that net’s eight-week winning streak. Among adults 18-49, CBS was third last Sunday night, 7 shares behind ABC’s “Commandments.” That epic film remains a powerful perennial, though its rating did come down 6% this year compared to its year-ago run. NBC has now gotten its two best Sunday 7-8 p.m. non-sports ratings since Jan. 17 from a pair of “Unsolved Mysteries” specials. Saturday saw CBS earn its highest rating for that night of the week since the World Series, thanks to the semi-final NCAA basketball tournament game between Michigan and Kentucky. The game itself finished 5% below the comparable Duke-Indiana game of a year ago. Friday went again to ABC in a breeze, though CBS got an encouraging start from the Shelley Long-Treat Williams sitcom “Good Advice,” the strongest CBS regular-series rating in the Friday 9:30-10 half-hour since “Bob” premiered last September. “Bodies of Evidence” joined CBS’ Friday schedule at 10 p.m. and improved by a meager 2% over what “Picket Fences” had averaged there this season. A special Tuesday episode did better, topping by 3 shares “Bodies’ ” best figures from last summer. Thursday went narrowly to NBC, which got a hint of how badly it’s going to miss “Cheers” next season. The net tried a “Wings” rerun at 8 p.m. instead of the usual “Cheers” rerun and immediately nosedived 3 shares below the worst figure “Cheers” has served up in that half-hour. “Seinfeld” continues to impress at 9:30, where last week it equalled its “Cheers” lead-in numbers despite a rerun episode following a “Cheers” first-run. “L.A. Law” also returned to the NBC lineup, equalling its fourth-best household rating of the season, and winning the 10-11 p.m. hour among adults 18- 49 (Daily Variety, April 5). NBC thus won the night in the 18-49 demographic by a more-than-comfortable 8 shares. CBS’ “Picket Fences” will have some building to do in the 10 p.m. hour. It started in the slot last week with CBS’ lowest regular-series rating there since Oct. 1. ABC got its best non-”Matlock” Thursday 9-10 p.m. rating since Jan. 7 from a special “The Commish.” Wednesday remained in ABC’s column (and by an astounding 11 shares among adults 18-49) thanks to “Home Improvement.” The alphabet net also got a good start from “Home Free,” up 7% over its “Wonder Years” lead-in. “Doogie Howser” hadn’t improved that substantially on “Wonder” since Dec. 9. And ABC’s “Sirens” has now hit a higher note than NBC’s competing “Law & Order” four times in four tries. After four weeks, CBS’ “How’d They Do That?” has averaged a strong 27% improvement over predecessor slot regulars this season. Also, CBS’ “48 Hours” has won its Wednesday 10 p.m. hour 17 times in its 22 airings there this season. On Tuesday, “David Copperfield” made the competition disappear, allowing CBS to win its 11th straight Tuesday. “Copperfield” levitated an impressive 8% above its ’92 rating and conjured up CBS’ best share that hour since the Winter Olympics back on Feb. 11, 1992. “Rescue 911″ took the 9-10 p.m. hour, thanks to the 30% ratings drop-off at ABC from “Roseanne” to “Jackie Thomas.”"911″ phoned in CBS’ highest rating that hour in five weeks. Fox’s “Tribeca” cooled by 13% in its second week, but still beat each “Key West” telecast in the slot since Feb. 2. Monday belonged to ABC and its Oscar coverage, which improved on its ’92 rating by 5% to top a 30 rating for the first time since 1984 (Daily Variety, Marcy 31). An “Above the Law” rerun had NBC’s best film rating versus an Academy Awards in six years.