An amazing piece of Americana as the producer puts it. The musical numbers are crazy memorable like Have Yourself a Merry Little Christmas and Zoom Zoom Went the Trolley. The colors are rich the sequences are very well crafted. The whole film is a giant spectacle of candy-like colors, sets, and production elements with a lot of emotional substance in the story too.
Judy Garland really does a great job of shining onscreen after setting the bar so high with The Wizard of Oz. Yet, in this film she's far more real a person than the placeholder everygirl object she is in Wizard.
The film shows how advanced cinematic technology is and Hollywood effects and sets. The Mega Movies are going to start appearing in scale. This is a change in format. Film is pushing out on the perimeters of modern entertainment to take the market to new heights and spectacle.