The bar frequented by Frasier and his friends is named Mahoney's as a tribute to the late John Mahoney.
David (Niles and Daphne's son) was named in memory of co-creator and producer of the original show, David Angell. David and his wife were killed in the first of two planes to hit the World Trade Centre during the September 11, 2001 attacks.
The character name of Moose (Jimmy Dunn) seems to be a tribute to the dog actor Moose who portrayed Eddie for the majority of the first 8 seasons of Frasier before his son Enzo took over the role for the remainder of the series.
Kelsey Grammer, Peri Gilpin and Bebe Neuwirth are the only cast members who reprise their roles from the original series as Dr. Frasier Crane, Roz Doyle and Dr. Lilith Sternin.
The busts in the cover page are (counter-clockwise from bottom front): Mozart, Shakespeare, Benjamin Franklin, Louis Pasteur.