Amazon&39's new digital music locker service.

Amazon got the jump on Apple and Google this evening with the launch of a much-anticipated digital music locker service that allows users to store their music on the Web and then listen to their collections on computers with a Web browser or on Android devices.

Amazon Cloud Drive allows users to upload their digital music files--either AAC or MP3 formats--at their original bit rate to Amazon servers for storage and playback on any PC, Mac, or Android device, where ever they are.

The Cloud Player for Web allows customers to listen to their music on any computer running Internet Explorer, Firefox, Safari for Mac, or Chrome. The Cloud Player of Android is a new version of the Amazon MP3 app and includes the full Amazon MP3 Store and the mobile version of Cloud Player. Customers can use the app to play music stored on their Cloud Drive and music stored locally on their device.

The Cloud Drive also allows customers to upload music, photos, videos, and documents, but those digital files are accessible only via a Web browser on a computer.

Customers will automatically start with 5GB of free storage, upgradeable to 20GB with the purchase of an Amazon MP3 album. Additional storage space can be purchased in plans beginning at $20 per 20GB per year.

"We're excited to take this leap forward in the digital experience," Bill Carr, vice president of Movies and Music at Amazon.com, said in a statement. "The launch of Cloud Drive, Cloud Player for Web, and Cloud Player for Android eliminates the need for constant software updates as well as the use of thumb drives and cables to move and manage music."

CNET reported last week that Amazon was working on creating a digital locker service for users' film and music libraries and might make an announcement as early as this week. Sources told my colleague Greg Sandoval that as of last week the online retailer giant had not obtained all the necessary licenses, but that Amazon might announce the service before all the negotiations were complete.

This evening's launch give's Amazon a leg up on Apple and Google, which are reportedly working on competing efforts.

Apple has reportedly been looking to expand its MobileMe service into a music storage and streaming service. However, Apple is supposedly looking at a fall release date to coincide with a revamped mobile OS with a greater focus on cloud-based services and other enhancements.

Meanwhile, Google has begun testing its Google Music streaming service for Web-connected devices with its employees--a sign that the much anticipated service is nearly ready to launch. A working version of the service was reportedly discovered after an installation of the Honeycomb version of the Android operating system on a phone. It's reportedly close to being ready to launch but is being held up by music licensing negotiations.

Amazon already has extensive experience with cloud services. Amazon stores electronic books on its servers for owners of the company's popular Kindle e-book reader. Kindle users can buy e-books from Amazon.com, download them to their devices from wherever they can access the Web, and Amazon will save the digital copy in the customer's digital locker.

Updated throughout the evening.