Centre Of Attention
Several scenes set in the hospital were filmed in the foyer of Cardiff's Millennium Centre. As a neat tie-in, the Centre was subsequently used to host the press screening of the episode. The party scene at the end was filmed at a dim sum bar just around the corner!
Former Casualty actress Adjoa Andoh went from playing a Cat Nun in this episode to Martha's mum Francine Jones in Series Three.
Little Shop Of Humour
New Earth is the first story to refer to a 'little shop', a running gag that would reoccur in both Smith & Jones and Silence In The Library. The Doctor likes a little shop...
If you look closely at the location at the start of the episode, you can still see traces of the words "Bad Wolf" on the tarmac, left over from filming The Parting Of The Ways.
Who's Sorry Now?
The Tenth Doctor's catchphrase, "I'm sorry. I'm so sorry," is first used in this episode.
This is the first Doctor Who episode to have an accompanying TARDISODE - a mini prequel teaser clip available to download to mobile phones and online.
Rose refers to Cassandra as "Michael Jackson", something she also did in The End of the World.
Not So New Earth?
Unrelated planets or systems called New Earth have featured in the television adventure Invasion of the Dinosaurs (1974), comic strips The Iron Legion and Dogs of Doom and the novels Time of Your Life and Synthespians™.
Feline races have featured in Doctor Who before. These include the Tharils in Warrior's Gate (1980) and the Cheetah People in Survival (1989).
Face To Face
Zoe Wanamaker makes her first on-screen appearance in Doctor Who here, having only featured as Cassandra's voice in The End Of The World.