Best Buy is joining Amazon, Google, and Apple in offering customers a cloud-based storage and streaming service for digital music. Using its “PlayAnywhere” technology, the Best Buy Music Cloud will let users upload their songs to the cloud, then stream the music across multiple devices, including Blackberry, Android and iOS.

But with stiff competition from the other big companies who’ve entered the cloud music locker space lately, can Best Buy offer something that will make customers use its service? Based on what’s available today, the answer is “probably not.”

In all fairness, this is a soft launch of the Best Buy Music Cloud, but users can sign up now. You can download the software onto your PC, and if you link your phone number to the account, you will get a text message linking to information about mobile apps – when they become available. The emphasis here should be on soft launch, as the missing mobile apps and problems with uploading files to the cloud suggests.

The Music Cloud software will scan your iTunes folder (and yes, that’s where your music has to reside for the app to work) and then upload files to the cloud. That’s a different process – and pretty cumbersome one at that – than the matching service that Apple’s soon-to-be released iCloud will provide. As with Apple’s new iCloud service, however, you will be able to store some music files locally, so that you don’t have to pay a data penalty for music you want to access frequently.

There are two pricing tiers for the Best Buy service: free and premium. The latter will cost you $3.99 per month. The latter, which the website calls “web+limited only” won’t let you stream music to mobile devices. But even more frustrating (and inexplicable, really): with the free service you can only listen to 30 seconds of the songs you have uploaded.

There aren’t a lot of other details about the service. No word on storage caps, for example.

Perhaps when this officially launches, Best Buy will have more information and a more polished app. As it stands right now, particularly with the other major players out there also building online music lockers, Best Buy’s cloud service just won’t fly.