This technique allows you to install Android apps before they are repackaged for the PlayBook. Most applications will work, but there are some Android apps that will not work, so far Angry Birds and Skype are two of the more popular apps that do not function correctly. As always rooting your device is an “at your own risk” activity, but if you’re going to do it, a step-by-step is always nice to have on hand.
How to install the Android Market and other applications to your BlackBerry PlayBook [link]
source: Android Central