When Meredith Delaney and Boris Steloff are embracing, she puts both arms around his neck, in the next shot her hands are touching his chest, then seconds later, back around his neck.
When the detective finds the earring on the floor near the murder, the back is still on it. Tough to lose a pierced earring from your ear with the back still attached.
After the title "Murder on Madison Avenue" shows, the camera moves to a long shot of Park Avenue. The Waldorf-Astoria & Pan-Am Building give it away.