http://smartphonenation.com/2009/07/download-the-new-blackberry-messenger-5-0-ota/
The new Blackberry Messenger includes:
Avatar Support – set your own avatar using the camera or saved photos on your device
GPS location integration – you can now set permissions so friends can always see your location, have to request it each time, or never can see it
Proximity Sensor – will let you know if you’re within a certain distance of friends
Set Coversation Subjects – this allows you to organize your convos on the main messenger screen and label them with subjects ot keep track of all your conversations
Homescreen Support – you can pin/sticky actual Messenger contacts directly to the homescreen for easy access