Scarecrow doing a handstand during her second performance.
In Episode 4, Carwash does a few backflips in succession across the stage.
Squirrel doing the splits during some of her performances, most notably in the final. Even more so when its revealed that shes the 56-year-old Bonnie Langford.
Just the fact that the majority of the dancers are actually in their 40's or 50's. It shows that you can still be a good dancer despite your age.
Big-Lipped Alligator Moment: At the end of Carwash's performance of "Singing in the Rain", someone in a pigeon costume comes onto the stage and offers Carwash a cone of chips. This is never brought up again, nor is it mentioned when he gets unmasked.
Captain Obvious Reveal: As soon as the possibility of Knickerbocker Glory being Craig Revel Horwood was brought up, it became obvious with their clue packages, especially in the semi-final. In fact, several viewers even guessed it from the first few episodes. Its probably why they ended up the first to be unmasked in the semi-final. And even for those who didn't guess correctly, it didn't take long for it to become apparent that he was actually a man Disguised in Drag.
One that happened within the same episode: In Episode 5, Jonathan Ross guessed that Squirrel could be Zoe Ball, only for Llama to get unmasked and revealed to be Zoe Ball instead. He even lampshades this.
During the first few episodes, a popular guess from the viewers for Knickerbocker Glory was David Walliams... and then he appeared as a guest judge in Episode 5, shutting that down.
One of the panel's guesses for Carwash was Howard Donald. Then in the final, it turned out that he was in the competition, but as Zip.
Memetic Mutation: In one episode, Davina wears some kind of white feather pressed against her hair, leading to people joking that a bird did something unpleasant in her hair.
Shocking Elimination: In the first episode, Viper/Jordan Banjo, a professional dancer was voted out after not only ending up in the bottom three, but also having the judges choose Beetroot, whom the viewers felt didn't really dance, over him.