There's an option in BBM 5.0 to change the pic your contact has chosen to a pic that YOU want. They don't see it, only you do. Just click the menu after you've highlighted their screenname while in BBM.
Edit-hold your finger over the lens and snap a pic. You'll have a perfectly black screen to replace their pic with.
2nd edit. Just set their contact pic to whatever you want, then uncheck this box.
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You didn't mention what device you're using. On my Tour (and my wife's Tour) it changes the BBM pic that shows up. Another poster said this isn't supposed to happen. It could be a glitch in the Tour's 4.7 OS; if it is, it's not the only one.
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