This is a very interesting question, and I think one that will either be positive or negative for RIM and/or Google.

On the one hand, I can see this increasing the value of the playbook to certain consumers, and gives RIM a huge repository of applications to launch with. This will likely be a selling point for some individuals that know what Android is, or are seeking it out.

Of course, it introduces problems. RIM is almost locked into supporting Android apps from here forward, as if customers expect this functionality and tie it to the Playbook brand, it may hurt the brand if they remove it.

It also reduces the differentiation between the Playbook and other Android tablets. This may actually be a good thing in the short term, as RIM would have a steep uphill trek to carve a niche out in this hugely competitive space.

The bad thing is, that developers knowing that they can target all Android tablets and the Playbook with a single APK would probably be reluctant to program one specifically for the Playbook. If I were an app developer, I wouldn't. What would be the point?

I see this as being great for the Android eco-system, but bad for RIMs efforts as the playbook becomes more-or-less another Android tablet. Unless they have a strategy to get developers to develop apps specifically for their OS (some cool functionality not available on Android), they may have made things far simpler on themselves by implementing their own port of the Android OS.

I don't have sufficient inside info to claim to know what's going on, or what should happen, but it strikes me that it would have been good for RIM to create a HIGHLY customized version of Android, with a bunch of RIM specific APIs, rather than a whole new OS with key Android components embedded.