New Landmark Greeted With Fanfare in Harbor A New Era Hailed On Festive Day Stream of Dignitaries and Curious Motorists Causes a Brief Traffic Jam OTHER HEADLINES Pontiff Adjourns Vatican Council and Honors Mary: Title 'Mother of the Church,' Shelved During Debates, Is Conferred by Pope: 3 Decrees Are Enacted: Ground Laid for Wide Shifts -- Paul Voices Hope for 'Next and Last' Session Rebels in Congo, Near Showdown, Shift Prisoners: 660 Belgians and Americans Taken From Stanleyville, Broadcast Reports Panel Opposes New F.B.I. Role in Johnson Guard: Cabinet Study Rejects Shift of Investigating Function From Secret Service: Warren Data Weighed: Creation of a 'Superchief' for President's Protection Is Also Turned Down Drug War Study Pressed By Army: Work on 'Humane' Weapons Goes On in Deep Secrecy Kennedy Epilogue: A Shocked Dallas Changing Its Ways 3 Railroad Unions Postpone Strike: They Heed Plea by Wirtz to Continue Talks -- Walkout Had Been Set Tomorrow U.S. Seeks Controls on A-Power Plants Sudanese Revolt Spreads in South: New Regime Seeks Peaceful Solution, but Raids Press Independence Demands Guerrillas Battered in Vietnamese Trap The sun shone, the sky was cloudless; bands played, cannons echoed up and down the harbor, flags waved, and thousands of motorists yesterday became part of the first--and perhaps only-- blissful traffic jam on the Verrazano-Narrows Bridge.