Research In Motion recently announced a new music-sharing service that is based on its popular BlackBerry Messenger platform. In a nutshell, for $4.99 per month, it allows users to share 50 songs through their BBM profile. For each BBM contact a person adds, they get access to another 50 songs (assuming their friend shares 50 songs, too). If you get bored of the 50 songs you uploaded, you can swap out up to 25 of them per month.

In theory, the service could provide you with access to thousands of songs if you have a lot of BBM contacts who share music via this new social-networking-cum-music-sharing idea. It allows for offline access by caching locally on the device, and offers interesting features such as which songs are most popular, and so on.

On the surface, the idea sounds neat. You get to share the music you like, and see the music your friends like. If everyone is lucky, their friends share good music worth listening to. But let's be real.

It's no secret that I am big fan of music. My MP3 library borders on the ridiculous, and consumes about 125 GB of space on (various) hard drives I have and in the cloud through Google Music and Amazon Cloud Drive. Through Amazon and Google alone, I have full access to my entire library of nearly 18,000 songs (all legitimately purchased, BTW). I was able to get the unlimited storage from Amazon for $5, and so far, Google Music is free.

Let me repeat that: Through Amazon Cloud Drive and Google Music, I can access 18,000 of my own song files for $5 per year.

RIM's offering costs $60 per year, which buys a nice hunk of extra storage through any Google account. The 50-song limitation is terrible. Even if I have 20 friends who share 50 songs each, that only provides access to 1,000 songs. Even if you have 50 BBM friends who agree to join this service, the number of songs available is limited to 2,500. Surely that's enough, right? Wrong.

Consider free (though ad-supported) services such as Pandora and Slacker. Each of them provides access to many millions of songs at absolutely zero cost. Slacker allows for on-device caching if you want to listen when on an airplane. Both also have social media components that makes it easy to share songs.

If you want to listen without ads or get the ability to skip tracks, it'll cost you $10 per month for the premium services. Same goes for Spotify, which recently launched in the U.S. For $10 per month, Spotify users get premium access to their own libraries, plus the libraries of their friends, both via the desktop and their mobile device. Which sounds like a better deal to you, $60 per year for 1,000 songs, or $120 per year for millions of songs?

Also, let's not forget that your friends' taste in music might suck. You could love rock and roll, and they might prefer something else.

While I give RIM credit for trying something with a unique angle, BBM Music is simply not a service I could ever agree to use due to its severe limitations. My guess is most other BBM users won't give it a shot, either.

Here is RIM's description of how the service works:

-- Build a personal music profile with 50 of your favorite songs. You can refresh your profile by swapping out up to 25 songs each month.

-- Invite your BBM friends to subscribe to BBM Music and to join your BBM Music Community.

-- With each friend that is added to BBM Music, you grow your music collection since the songs from the profile of each BBM Music friend are available to you at any time.

-- Up to 50 tracks from your personal profile are shared with your BBM Music Community, and each member of your community shares up to 50 songs from their profile with you.

-- Enjoy a truly social community-based music experience--the more friends who join your community, the more songs you can listen to.

-- Easily discover music that your BBM Music friends are listening to, and comment on your friends' songs and playlists.

-- You can create multiple playlists from music in your profile as well as all of your friends' profiles, and with one click you can shuffle the entire collection of music from your BBM Music Community. You can even see which friend contributed each song while it plays.

-- Within your BBM Music app, you also see a visual timeline that shows the recent updates of all users within your community. It gives you a chronological view of community updates, including who added new friends, which songs were added or removed, which playlists were created and what comments were made by your BBM Music friends.

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