The steamboat is based on Disneyland's Mark Twain.
Another Disneyland nod is the name of the band Louis ends up playing in, "The Firefly Five plus Lou", being based on "The Firehouse Five plus Two".
Another Disneyland shout-out! In the end credits, there's a shot of a run down shack in the middle of the bayou with a rocking chair on the front porch and a little rowboat next to it. This looks suspiciously familiar to the little shack with the old man in a wooden rocking chair in the beginning of the Pirates of the Caribbean ride, which just happens to be located in New Orleans Square.
The Other Wiki is currently of the opinion that "Evangeline" the star is a direct shout-out to Henry Wadsworth Longfellow's poem about love of the same name. It's possible considering that in both works, Evangeline's love dies while looking at her, being glad that she's there to oversee his final moments.
"Evangeline" is the name of an old Cajun (Acadian) Fairy Tale.
Mama Odie's put-upon snake sidekick: a benevolent version of Sir Hiss from Robin Hood. Or Kaa?
Numerous Shout Outs for New Orleans natives.
Naveen: My friend, we are from a place far, far away from here. Ray: Go to bed!! Y'all from Shreveport?
Anyone else notice that during Facilier's song and dance number he strikes a pose very reminiscent to the recently deceased King of Pop? In this video, it is confirmed Dr. Facilier was inspired by Michael Jackson as well as Jim Carrey, Jack Lemmon, and Usher. Oh, and when creating Dr. Facilier, Bruce W. Smith was imagining what the love child of Captain Hook and Cruella de Vil would be like. He's also definitely channeling some Cab Calloway in his moves, and the first part of his song is somewhat reminiscent of "Minnie The Moocher", and Naveen's dancing shows influence from both Fred Astaire and Gene Kelly.
Louis references Louis Armstrong and Sidney Bechet in "When We're Human". Plus:
Ray thinks Evangeline (a star) is a firefly. Later, a despaired Tiana tells him that it's just a ball of gas far away. This alludes to a scene in The Lion King where Pumbaa asks Timon what those "sparkling dots are up there". A confident Timon tells him that they are fireflies that got stuck in the sky, and Pumbaa is embarrassed to admit he always thought they were balls of gas millions of miles away. This movie shows Timon might have been right.
After Ray joins Evangeline as a star in the sky, it's made a bit clearer that Evangeline is the second star on the right.
Theres a scene where Charlotte dances with Naveen. It uses the bit of animation previously seen at the end of both Sleeping Beauty and Beauty and the Beast. Part of the point of this scene is to evoke the scene where the Prince dances with Cinderella since Charlotte wishes to be such a princess. Her gown is also based off of concept art from Cinderella.
Ray ends up dying, and we see him put to rest at his funeral. Consider that John Lasseter is a huge Studio Ghibli fan, and what do you come up with? Grave of the Fireflies.
Look carefully during Tiana's Dream Sequence song 'Almost There'. The piano player is none other than Duke Ellington.
When Tiana was wearing the blue princess gown, is it me or did her necklace look a LOT like the necklace Pocahontas wears?
At one point when Naveen and Tiana first meet Louis, he pulls on some Spanish moss similar to how Mad Madam Mim pulls her hair in "The Sword and the Stone".
Lawrence getting his head stuck in a tuba may be a possible shout out to Beauty and the Beast, where the same thing happens to Lefou.
There's a scene from Ma Belle Evangeline during Naveen and Tiana's dance where Ray lights up the lilypads, leaves, and dandelions in a manner very similar to the Nutcracker Suite from Fantasia.
During the credits, Naveen and Tiana (as frogs) are sitting on a leaf, and go down a water fall. Naveen plucks a white water lily from the side, giving it to Tiana, copying a nearly identical scene to the magic carpet ride from Aladdin. Not long after, two birds pull apart a curtain of vines, mirroring a scene from The Little Mermaid, onto a scene with Tiana and Naveen walking over a bridge similar to one from Cinderella. The swans making a heart with their necks also might be a shout out to the ones from Cinderella III. Whew.
Also, there was a man dressed as an octopus with several glasses of wine. He and teh lady who he got them from are shout outs to people who worked on the movie. When the man sees Tiana and Naveen go past with Stella chasing them, he dumps out his wine. The scene, what with the expression and the mannerisms are similar to those one man from The Aristocats makes when seeing a mouse chase a cat. let's call it a day, shall we, and just give this shout out section its own page.
It's possible that Naveem and Tiana transform after their froggy wedding is a Shout Out to the way that Odette's transformations were animated in The Swan Princess.
Several other music scores and minor mannerisms from earlier definitely put it in mind.
The scene where Tiana walks in on Charlotte and Lawrence in disguise as Naveen's wedding has a striking resemblance to the scene where Ariel walks in on Ursula, disguised as a woman, with a hypnotized Prince Eric.
The gag with the drummer at the Mardi Gras party is possibly a shout-out to Snow White and the Seven Dwarfs, in which something similar happened when Dopey tried to catch a fly while playing a makeshift drum set.
At the end, when Facilier is about to be taken down by his "friends", look at the three masks when they say "Are you ready?". Don't they remind you of three hyenas? Specifically, compare the part with the one on "Be prepared" when the trio sings "Yes, our teeth and ambitions are bared". Also, Facilier calls them "friends", only to be proved otherwise, the same way Scar call the hyenas friends before his demise.
The morning after Naveen and Tiana are turned into frogs, she calls out to him saying "Rise and shine, Sleeping Beauty!" Coincidentally, this same thing was said to Mulan by Mushu.
Throw It In: Originally, the plan was for Naveen to say "That's new" after his vocal sac inflates suddenly in a surprised tone of voice (i.e. "Whoa, that's new.") However, Bruno Campos said the line in a suave tone of voice, making the scene arguably much funnier (especially since his new tone of voice makes it sound more like "That's a new feature", in other words, that he's trying to pretend he already knew about it).