Rivette noted its magnificent ambition and I can't say I disagree, especially given the troubled production history. Knowing about Garland's personal struggles (and how the people involved in the production came together for her) makes the narrative particularly heartfelt. The final dance number was the last thing shot, a month after production finished, and ranks up there with the greatest.
A classic musical. Kelly's newspaper dance, "You Wonderful You", the "Get Happy" routine, etc. Walters makes possibly the best film of his career (Easter Parade and Lili are close contenders). Garland is clearly suffering but, ever the trooper, pulls off one of her most brilliant all around performances. Only weak spot is the stupid "Heavenly Music" routine making fun of hillbillies. Its a wonder it wasnt scrapped.