Due to the difference in age between Caitlin from Pokémon Platinum, HeartGold and SoulSilver and Pokémon Black and White, it can be inferred that the Generation V games take place even as many ten years after the events of Pokémon Diamond, Pearl and Platinum.
In Pokémon Platinum, Caitlin appeared as a brunette, but she now has blonde hair.
It is said by a NPC in the Battle Castle that Darach has feelings for Caitlin, but he refuses to let them show.
It is revealed in Pokémon Black and White that Caitlin is described to have Psychic powers which she had trouble controlling in the past due to her explosive temper.
With the exception of Metagross and Bronzong, all of Caitlin's Pokémon are Female.
3 of her 6 Pokémon are Dualed-Typed.
With the exception of Metagross, all of her Pokémon know the move Psychic.
Caitlin is the third Elite Four member to use Psychic Pokémon (Will and Lucian being the other two).
Caitlin is the first female Elite Four member to use Psychic Pokémon
Caitlin is the second character from a previous game to join the Elite Four. The first was Koga who joined the Johto Elite Four. Bruno does not count because he was a member of both the Kanto and Johto Elite Four.
Caitlin is the youngest one in the Elite 4.
Caitlin's team seems to be based off of sleeping. Reuniclus is a good dream, Musharna is the sleeping person, Sigilyph is a dream catcher and Gothitelle is the night gown.
Her rematch team may also be based on sleeping. While Bronzong represents a bell, it is unclear what Metagross has to do with sleeping though it could be bed.
Because of her long blonde har, her night cap and slender appearance, Caitlin bears a slight resemblance to the Leiji Matsumoto character Maetel.
She is the sixth known Psychic, or at least, trains Psychic Pokemon in the games. Sabrina, Will, Tate, Liza, and Lucian are the others.