Features:
Enhanced SMS -Allows for a conversational chat-like user experience with a single contact list for the most personal mobile-to-mobile communications. Note: BlackBerry? Device Software 5.0 and later is required for the SMS functionality.
Avatars - Users can choose a picture from the BlackBerry Smartphone gallery and save it as their personal avatar, which will be seen by their contacts. They can also view other avatars in the contact list and zoom in on the avatars of contacts participating in a conversation by selecting "View participants."
Large Media File Transfer - Users can send/receive large file transfers up to 6 megabytes for pictures, files and audio. Note: BlackBerry Device Software 5.0 is required to receive large media files.
Enhanced Group Functionality - Allows for the ability to update, share & communicate with a subset community.
Bar-code Identity - A user can add a contact to the BlackBerry Messenger contact list by displaying a 2-dimensional bar code that invitees can capture with their device cameras.
Reliable Contact Backup and Restore - Contacts are backed-up on a server and do not require the need for BlackBerry? Desktop Manager.
http://appworld.blackberry.com/webstore/content/3729