I also found you can add bbm contacts via email instead of pins. When I replaced my last curve and did a google sync, it brought the emails to the device, but no pins. So I tried to add anyway and I was able to add each contact strictly by email. I no longer have to be bothered with ever-changing pins when emails always stay the same!
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The advantage? Multi-person conversations. Believe me, BBM makes everything better when you're stuck in a boring presentation / meeting and can have a group chat with all of your friends around the table via blackberry
I just use it to talk to my fiance faster and type longer messages than a text. Anything else I'll send a text. Its also quicker to use to send pictures through.
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