One thing to note is that this is only available to new users and those still currently in their trial period. If you have already starting your subscription payments, unfortunately you are no longer eligible for the free service promotion.
The latest update to BBM Music is to version 22.214.171.124. With this update comes a whole lot of new features including subscription gift request and the ability to invite Facebook and Twitter friends.
Don't forget this offer is valid if you download during the month of February, so if you're looking to give BBM Music a try, now is the time.