When Will Amazon's MP3 Store Come To Mobile?

Music is a huge seller in the mobile marketplace.  Why carry a walkman or a discman when your phone can deliver high quality music to your £3.99 headphones?  Hear a song you like on the radio, in a concert, from a busker singing - a few clicks and it's on your phone ready to play.

At the moment, MNOs* rule the roost in terms of mobile music sales.  Customers don't want to type in their credit card number on a phone's keypad.  They're also wary of risky premium rate, reverse billed SMS.  They want ensured compatibility. That's why MNO portals do so well - the charge goes straight on the customer's bill.  If there's a problem, they know who to ring and complain.

Amazon, I think, changes that preconception.  A customer probably already has a relationship with Amazon and trusts them.  A customer can go straight to Amazon's Mobile Site, log in and then purchase using the infamous 1-Click.  A little up front complication (the logging in) is off-set by Amazon's wishlisting, giftlisting, customer reviews, recommendations and silky-smooth interface.

Could Amazon change the mobile purchase marketplace in the same way that they revolutionised book-selling?  MNO portals are traditionally locked gardens (only MNO customers get access; as opposed to walled gardens where customers can't get out).  Will competition from Amazon - and their inevitable imitators - radically alter the market?  We've already seen DRM dropped from mobile music, a range of new subscription plans, and complex bundles - what next?

But, for now, potential Amazon customers simply see "This mobile site does not currently support the purchase of this item."  For how long, I wonder...?

*Yes, I work for one. No, I don't speak on their behalf.