In all episodes following this one, the replaced tile over the fireplace (broken by the bullet accidentally fired from Martin's (John Mahoney) gun) can be seen to be a shade darker than all the others.
The 'Miss Right' story that Frasier (Kelsey Grammer) recounts to Lilith (Bebe Neuwirth) over drinks refers to a "date from hell" he had in The Placeholder (2003).
Lilith's hotel room number is 906.