In this episode Rhoda makes a quip about an erasure of information from a tape recording. This was a subtle dig at the revelations before the Watergate panel, when it was discovered that an 18 and one-half minute gap existed in one of the Oval Office recordings.
While at Mary's apartment planning the pilot episode of the talk show, Sue Ann Nivens (Betty White) said she won a baby talent contest at the age of six doing an impersonation of child star Shirley Temple, then she starts to sing "On The Good Ship Lollipop". Shirley Temple was in fact six years old when she performed the song in 1934, however, Betty White was six years older than Shirley Temple and Betty would've been twelve years of age in 1934.
When Sue Ann is dancing while performing Good Ship Lollipop, she dances too far out and you can see the tape on the floor indicating where a camera should be placed.