PlayBook owners over on the CrackBerry forums have discovered that, after applying a new BlackBerry Bridge v1.0.0.83 update, they were able to use BBM on their BlackBerry PlayBooks. The feature reportedly only works with BlackBerry 6 devices right now, although there are rumblings that a BlackBerry OS 5 version is in the works as well. You’ll also need to update your BlackBerry Messenger application to the newest version first, and that should be available from RIM’s BlackBerry Beta Zone. Unfortun...