Dawson Casting: Mildly. The film does avert the trend of having a teen or young adult play Alice. Alice's voice actress, Kathryn Beaumont, was thirteen when the film came out and therefore probably about eleven or twelve when she recorded her lines. Kathryn Beaumont was also the physical model for the character. As a result, Alice is drawn looking like she's around eleven or twelve, whereas she was seven in the book. It's generally accepted by Disney fans that Disney!Alice is the age she looks rather than her book age.
Development Hell: The entire concept of a film adaptation of a story such as this was in development since the 1930s.
Ed Wynn as the Mad Hatter, Jerry Colonna as the March Hare and Verna Felton as the Queen of Hearts.
Bill Thompson, the voice of Droopy, plays the White Rabbit.
A couple of uncredited regular Disney singing voices can be heard; one of the lead singing flowers in "Golden Afternoon" is voiced by Marni Nixon, who can be heard singing in several classic movies, including Cinderella(lead vocals), West Side Story(Maria's singing voice) and My Fair Lady(Elisa Doolittle's singing voice). Meanwhile, the card guards singing "Painting the Roses Red" were voiced by Disney's in-house vocal group The Mellomen, and the bass voice in that number is the distinctive Thurl "You're a Mean One, Mister Grinch" Ravenscroft.
Talking to Himself: J. Pat O'Malley voices both Tweedle Dee and Tweedle Dum and all of the characters in the "Walrus and the Carpenter" segment. Justified because the Tweedles are twins and are the ones reciting the "The Walrus and the Carpenter" poem.
Bill Thompson voiced the White Rabbit and the Dodo. Most of the Dodo's appearance in the film consists of him having a conversation with the White Rabbit.
Apparently, the Cheshire Cat's recitation of the opening lines of "Jabberwocky" was to give way to an actual encounter with the Jabberwock itself, voiced by Stan Freberg. It was trashed for evidently being too scary.
Concept art was made of the Jabberwock, the Bandersnatch and the Jub Jub Bird, too. The Jabberwock had fiery eyes, the Bandersnatch had a long neck and a net for a tail, and one of many concepts for the Jub Jub Bird survives as the vulture-like "umbrella birds" that gave Alice a Death Glare when she interrupted their bath. Another concept for the Jub Jub Bird was a large eagle-like creature. The designs for the Bandersnatch and the Jub Jub Bird can be seen here and one for the Jabberwock and another for the Jub Jub Bird here.
An earlier adaptation was planned for the thirties. The storyboards were done by the talented British artist David Hall. It was a bit closer to the book. It was, once again rejected for being too scary. Amongst the concepts from this version was the Mad Hatter and March hare chasing Alice with a knife and scissors, the Cheshire Cat with hundreds of sharp teeth, and Alice nearly beheaded by a grinding gear. See the ending here
Janet Waldo, best known as Judy Jetson, was considered at one point to voice Alice. She would later voice Alice in Hanna-Barbera's own version of Alice in Wonderland, televised in 1966 over ABC.
There were a ton of cut songs composed for this film (over thirty according to some sources). A few were reworked into songs for other projects. For example "Second Star to the Right" and "Never Smile At A Crocodile" from Peter Pan was going to be "Beyond the Laughing Sky", sung by Alice and "Lobster Quadriddle",from the late 30's version. There were also a couple of cut songs for the Cheshire Cat and Mr. Caterpillar; the Cheshire Cat got "I'm Odd", which was to sum up his Blue and Orange Morality and Cloudcuckoolanderness, while the Caterpillar got "Dream Caravan", which portrayed him as a Dream Walker and had a ridiculously catchy tune...
Another early plot idea involved Dinah getting lost in Wonderland and getting turned into the Cheshire Cat. Alice, the cat, the Mad Hatter, and the March Hare were to go on a journey together climaxing with Alice's arrest by the Queen. In the end, the Cheshire Cat redeems him/herself and is turned back into a real cat and escaping with Alice for a happy ending.
In 2004, Disney used this movie to launch a new collection of 2-Disc DVDs, the Masterpiece Editions. Eventually, the other movies Disney announced for inclusion in this collection received 2-Disc DVDs bearing different banners (most of which commemorated the respective movie's anniversary). Disney struck the final nail in the Masterpiece Edition line when they re-released Alice in Wonderland as an "Un-Anniversary Edition" to promote the Tim Burton movie.
If you're wondering, this leaves five members of the cast. Of the five, one has an OBE for her acting, one was in The Illusionist, one was in 28 Days Later, and one graduated from Oxford Drama School. Only one member of the cast is not at least recognizable or otherwise awesome.