At one point the falcon was supposed to have an army of pigeons as his minions.
After the September 11 attacks in 2001, shots of the World Trade Center were digitally removed from all background shots of the New York skyline.
The Balto statue appears in this movie as Stuart crashes his plane. Balto was a sled dog that, in 1924, saved the population of Nome, Alaska, by carrying the diphtheria vaccine.
The whole negative of the film was digitized at 4K resolution and all CGI work integrated digitally.
When Stuart is carrying the "injured" Margalo into the house, he mentions that he races boats. This a reference to the previous film, as well as the winning boat shown in George & Stuart Little's bedroom.