Barge- Janus for digital music distribution will have an uphill battle upon it's release. There will already be 10-20 million iPods having been purchased, and I doubt if all those customers will be looking to replace their iPods(let alone all the additional soon-to-be iPod purchasers with the incredible momentum Apple has built in this space). People have not just purchased the iPods themselves, but tend to have significant additional onies involved in their iPod "peripherals"(Bose Sound-Docks, auto connection and charging systems, etc.)
Rob Enderle can predict away, but I'm predicting that Janus will have to scratch and claw just to gain a foothold, and it will not dominate --Stay tuned!
John