Over ten million songs have been purchased from iTunes Music Store since its launch four months ago, Apple has revealed.

The ten millionth song to be downloaded was Avril Lavigne’s Complicated. The landmark means more than 500,000 songs per week have been downloaded.

Apple's success has sparked a wave of rival services, notably from Sony, as well as Microsoft's MSN Music Club. Virgin is also planning to sell new tracks online weeks before they hit the shops.

There's still no indication when Apple will launch an iTunes Music Store in the UK.

UK band Coldplay is one of the top-selling bands on the iTunes Store. Band front-man Chris Martin said: "It's clear Apple has delivered a working and successful platform for music fans to discover artists, and purchase both albums and single songs instantly with ease. We embrace these efforts enthusiastically and see them as the future of our business."

This week's Macworld Online Reader Poll is asking how readers download music. Do you use iTunes, peer-to-peer, a service supported by Mac user Peter Gabriel's OD2 company, or do you prefer vinyl? Vote in the poll in the area to the left of this page, or have your say in the debate.