As The VIllage Voice stated, this is the "Citizen Kane of jukebox musicals," but it's more than that. It is an evocation, a memoir of a brief moment in time when the band that would change the world was still just four lads from Liverpool, not yet overwhelmed by success and excess (something that's quite evident in their frenetically overdone Help!, made only a year later). The wise choice of B&W photography make it timeless, and the dry wit of Lester's direction and the performances make it watchable today. Look at any other of the similar films that followed from the likes of the Dave Clark Five, Herman's Hermits and the Monkees, and realize how difficult such a film is to make, and how successful this film was at catching lightning in a bottle.
Names in parentheses are from the script.
Thanks to Gerald Lovell, Movie Dude, AgedAD and philly for helping identify so many extras, and cornershop for spotting Barbara Murray in the newspaper!