Having known Björk's music for a while, it is easy for me to understand where Medúlla's perspective comes from. Her endless need to reinvent herself, spinning world after world out of each project's sonic ashes, makes sense to the listener that hears the intimacy in songs like 'Pagan Poetry' and 'Jóga,' or the raw intensity in 'Hidden Place' and 'All Is Full of Love.' To the casual ear, though, this latest album may sound more like a series of a capella experiments, warmups, and even alarming mistakes. It is a fascinating listen, but an alienating one for the uninitiated.

Her spectacular first single, the Athens Olympics debuted siren call 'Oceania,' may have impressed many and confounded a great many others (Poor Katie Couric!), but her decision not to release it commercially is telling of her idiosyncratic view of music in general. Songs like 'Triumph of a Heart' and 'Mouth's Cradle' are both instantly recognisable as patent Björk magic and incredible sonic journeys, but digressions like 'Ancestors' and 'Miðvikudags' (Icelandic for Wednesdays) may confuse or even frighten. Her interest in paganistic, primal grunts and whistles is compelling to hear about, but disarming to listen to. That, in general, is the sense one will be left with after listening to most of these songs, sadly. But there are a number of worthy gems to be found, 'The Pleasure Is All Mine' and the e e cummings-based 'Sonnets/Unrealities XI' being remarkable examples.

Björk is a leader in her field and a master of innovation. But Medúlla is a departure many fans will have a difficult time following along with.

Look for the second single, 'Who Is It,' to come out on October 25.