As expected, Susan Winston has signed on to run "CBS Morning News," but she won't jump in as day-to-day executive producer for a while . . .

The former executive producer of ABC's "Good Morning America" from 1981 until 1984, when that show was at the top of the heap, indeed the king of the hill, in the morning network race, will join CBS May 5 with the title of executive director of Morning News planning . . .

Apparently, that means she'll spend a few weeks becoming acclimated to the new network, all the while figuring out (CBS News hopes) what should be done to get "Morning News" out of its perpetual third-place ranking in the morning race . . .

Meanwhile, Executive Editor David Corvo will continue as acting executive producer, as he has done since Johnathan Rodgers left the show March 16 to become vice president and general manager of WBBM, the CBS station in Chicago . . .

Winston could take over in June . . .

Winston got fed up with the grind at GMA in 1984 but then-ABC Sports President Roone Arledge prevailed on her to take a producer's job with the Summer Olympics before ankling the web . . .

She later joined Paramount to work on the pilot for "America," the syndicated magazine show that died after a few months . . . and currently heads Susan Winston Productions in California . . .

The regular CBS Monday night lineup beat out the movies on ABC and NBC with a 17.8 rating and a 28 percent audience share between 9 and 11 p.m., according to national Nielsen figures . . .

"My Two Loves," starring Mariette Hartley and Lynn Redgrave (as one of her two loves) averaged a 17.5/28 percent audience share. "The Annihilator" on NBC did a 14.1/23 . . .

Heavens to Betsy! For the first time since 'way back in February 1982, "NBC Nightly News" and "CBS Evening News" last week tied for first place in the network news competition . . .

I mean, we're talking both ratings AND shares, here, TV Column fans (twice since mid-February of this year, they've tied in shares but that's Not Quite the Same) . . .

For the week ending April 4, "NBC Nightly News With Tom Brokaw" and "CBS Evening News With Dan Rather" tied at 11.8 rating and 23 percent audience shares. "ABC World News Tonight With Peter Jennings" wasn't all that far behind, at 10.9/21 . . .

And to think that only a few weeks ago (the week ending Feb. 28, to put a fine point on it) we were all celebrating "CBS Evening News' " 200th straight week in first place! . . .

Dare we call the rivals for Their Interpretation of this Latest Development? Let's do, Airwaves, you wicked, wicked man! . . .

Says CBS spokesperson Ann Morfogen: "First of all, because of the NCAA basketball championship on CBS Monday night, 10 West Coast markets didn't carry 'Evening News' at all and the rest aired it at 5:30 or otherwise very early. And Monday night is 'Evening News' strongest night of the week . . .

"There is no question that Dan is the premier anchor and that we have the dominant news broadcast and the most respected news broadcast. And you have to remember the 'halo effect' of all of NBC's other successes right now -- in primetime and the 'Today' show, factors like that. And, no. No changes are planned" . . .

Says an NBC spokesperson, who declines attribution: "People are saying 'NBC Nightly News' is doing well because of all the on-air promotion the network gives the show. Well, during the random week of March 16, ABC ran 39 primetime promos for 'World News Tonight,' CBS ran 25 for 'Evening News' and we ran 22 for 'Nightly News.' " . . .

Local representatives of the National Academy of Television Arts & Sciences have sifted through 358 entries from local TV stations in anticipation of this year's local Emmy awards . . .

Now NATAS chapters in Boston, Philadelphia and Miami will judge the entries. Nominations will be revealed in mid-May and the winners will be announced at a banquet here June 21 . . . Also in the News

President Reagan has signed the Consolidated Omnibus Budget Reconciliation bill, which includes a provision authorizing appropriations for the Corporation for Public Broadcasting through fiscal year 1990. . . .

Under H.R. 3128, CPB authorizations will rise from $200 million in FY87 to $254 million in FY90 . . .

Today is the day that high school seniors all over the country will learn if they've made it to the college or university of their choice . . .

"The MacNeil/Lehrer NewsHour" tonight will air a unique 15-minute "mini-documentary" on how the admissions process works at Williams College, in Williamstown, Mass. . . .

NPR reporter John Merrow and a camera crew were permitted to film the deliberations at a Williams admission meeting for three days as the decisions were being made . . .

Among the features: a frank discussion on admission of an alum's child (whose chances were twice as good as anybody else's going in, because 11 percent of the college budget comes from alumni donations) . . . and an argument over admission of a disadvantaged girl whose grades aren't up to Williams' tough standards but who displays leadership qualities . . .

A spokesman for "MacNeil/Lehrer NewsHour" says it's a first, admission process-wise, for TV . . .

Which reminds us, somehow, that Christopher Ramsey has been named director of public affairs for MacNeil-Lehrer-Gannett Productions . . . of which the "NewsHour" is one . . .

And from our Better Late Than Never file: Rona Barrett departs "Entertainment Tonight" April 20 to "pursue other projects" . . . TV Ratingzzzz

With a scant two weeks to go in the Regular Season,it was NBC, CBS and ABC doing their regular 1-2-3 finish again for the week ending April 6 . . .

NBC had a 16.7 rating and a 27 share, CBS was close with 16.5/26 while ABC trailed at 14.3/23 . . .

NBC's "Beverly Hills Madam" was 22nd for the week, CBS' "Falcon Crest" returned in a tie for 24th with NBC's new "You Again?" and NBC's "All Is Forgiven" was 35th . . .

ABC's "Mr. Sunshine" was 39th, ABC's "Blue Thunder" movie tied for 44th with ABC's "Charley Hannah," CBS' "News at 11" was 47th and ABC's "Pleasures" was 48th . . .

NBC's "Stingray" was 51st, CBS' "Fast Times" was 56th, CBS' "Mary" was 57th, ABC's "Joe Bash" was 58th and CBS' "Morningstar/Eveningstar" was 60th . . .

CBS' "Foley Square" and NBC's "Alfred Hitchcock Presents" tied for 61st, just missing the Final and Presumably Fatal Five . . .

Which included, in order, CBS' "Tough Cookies" in 63rd, followed by NBC's "Punky Brewster"; NBC's "Fathers & Sons"; ABC's "Diner" movie; and ABC's "Fall Guy," which took a brand new episode and still managed to finish 67th and last for the week . . .