Research in Motion annoucned that its music-sharing application for its popular messaging service will be available for downloading in the U.S., Canada and Australia today.

BBM Music allows BlackBerry users to select 50 songs from a catalog of of tracks for their personal playlists. BBM users can share songs from that list with friends who use the instant messaging service. The more BBM friends with BBM Music Premium subscriptions a user has, the more songs he or she can share.

With BBM Music, users can grow and keep their music selection fresh by swapping songs every month and by inviting friends to gain access to their music. When users invite friends to BBM Music, they get access to their friends' musical playlist; they can build new playlists that include their songs and their friends' songs, they can comment on their friends' music and they can start a chat with any of their BBM friends from within the BBM Music app in real time.

Users can also cache their BBM music (or save music to their microSD card) for offline listening.

RIM is offering a Premium Subscription version and a Free Subscription version - here's what those options include:

PREMIUM SUBSCRIPTION: The Premium 'full track' BBM Music experience is available for a monthly subscription of $4.99 USD ($4.99 CDN and $5.99 AUD). The Premium version will feature a free Premium trial offer - users can use all the features of a Premium subscription for a limited time.

FREE SUBSCRIPTION: There will also be a Free subscription to the service that delivers the same social experience as the Premium subscription, but with 30 second song previews versus full song tracks. After the Free Premium trial offer period ends, users can opt to continue using BBM Music without a paid subscription by using this Free subscription. Users can also upgrade from a Free subscription to a Premium subscription at any time.