Throughout the series, the women's restroom at Cheers is always the first door on the left (when entering the hallway from the front), while the men's is the second. They are reversed in this episode.
The characters talk of it being 30 degrees outside and Nina waits at the bar until the heat is fixed in her apartment. Yet, during a cutaway scene to the outdoors, the sky is bright and the leaves are green and full. Uncommon for Boston in the winter.