Last week there was rumor of RIM possibly launching a music service tied up to their BlackBerry Messaging.  Today, RIM put that rumor to rest as they unveiled BBM Music.

BBM Music went on trial for free in UK, US and Canada on Thursday.   The music cloud service is provided by Omnifone, the British music service company that has licensed 10 million tracks from all available genres.

The service offers unlimited playback of songs with 50 songs users, and can keep in their cache along with offline access.  Users can swap 25 songs per month in and out of the music library or share with their buddies.   RIM also offers expansion of song allocation when users invite more people into the service, kind of like those old pyramid schemes.  The time-line based BBM view of the world will show your friends’ music activities so users can also keep track of what their buddies are listening to.  When the service goes live, meaning it has gained enough users, it will no longer be a free service, and will cost $4.99 per month in the US.  The UK price has not been announced yet.

RIM aims to roll out the service in 18 countries within the year.  BBM Music will be competing against Spotify, which has 1.4 million US subscribers with 175,000 paying customers.  Spotify also has a bigger market in the UK, with 4.67 million users and 1.54 million paying subscribers.  Rhapsody is also a top contender with 800,000 paying subscribers and a series of partnerships for extended, cross-device access portals.

RIM is banking on the fact that people around the globe deeply appreciate BBM and they are expecting that BBM Music will be accepted the same way.

“More than 45 million customers already love the social communication benefits delivered through BBM and we are thrilled to be extending the experience into a uniquely social and interactive music service,” said the RIM co-chief executive, Mike Lazaridis.