'Magical girl' is a genre I haven't indulged in very much, so practically speaking Puella Magi Madoka Magica was a first look into an unfamiliar tradition. Lack of familiarity, however, engenders a neutral viewing experience, where the job of an anime critic becomes almost pure analysis through virgin eyes. Of course, comparing Madoka to something is inevitable, but without a thorough understanding of shows in a similar vein, any comparisons I draw risk being poor ones. Here's what I know for certain: Madoka Magica became an instant classic, receiving universal acclaim for its innovations as both an original anime work and an unparalleled contribution to the magical girl genre. Calling it a 'magical girl' anime, in fact, calls into question what it means to be a part of the genre.
Source: Crunchyroll. Copyright Shaft, Aniplex.