Apple's iCloud service is perhaps the company's most interesting announcement today at WWDC. Long rumored as a music streaming service, Apple's take on cloud computing is better described as a synchronization platform and only a fraction of it involves music. Starting with iOS 5, many of Apple's native applications will support iCloud, facilitating the automatic synchronization of your contacts, calendar, mail, documents, photos, music, books, apps and backups.

Such content is bounced to Apple's new data center in rural North Carolina and shared between your other devices. For instance, if you take a picture, the image will be automatically uploaded to your iCloud account and downloaded to your iPad and MacBook. Many iCloud-enabled applications have their own unique twists -- such as sharing calendar data with your spouse -- but the music-specific portion of iCloud is particularly fascinating compared to the competion.

Instead of being a separate music subscription service, iCloud essentially augments the functionality of Apple's existing iTunes platform. Along with offering access to previously purchased music across your hardware, the service will automatically download newly purchased songs on up to 10 devices. Additionally, for $24.95 a year, Apple will offer a service called "iTunes Match," which will let you import non-iTunes songs and download them across all your devices.

Although it might seem pricey, iTunes Match presents several immediate benefits. Unlike competing cloud storage services, iTunes Match can scan your entire library and compare it against some 18 million songs in Apple's database. Those that are matched will become immediately available for download as if you've purchased them via iTunes, cutting out the entire process of uploading the files and automatically upgrading your lower quality songs to 256kbps AAC files.

We think many users will appreciate iTunes Match, even if they only sign up for one year to import a bulk of their library. Songs not available in Apple's database will have to be manually uploaded to your iCloud account if you want to sync them across your devices, but this doesn't cost anything. Apple provides 5GB of free storage -- just like Amazon -- but pictures and iTunes songs don't count against this limit and we imagine data can be cleared once it's done syncing.

It's worth noting that iCloud will replace Apple's current $99 MobileMe service. Besides iTunes Match, all other aspects of iCloud will be available to users free of charge. That said, we would expect Apple to eventually introduce paid storage capacities beyond 5GB. Although iCloud won't be available in its entirety until this fall, you can experience a beta version of the music portion with iOS 4.3.3 (released last month -- check your Store settings) and iTunes 10.3 (released today).