The process is going to take a while, though. A Research In Motion VP explained how it's going to work over breakfast at the BlackBerry Developer Conference. Apparently, the idea is to first launch BlackBerry OS 7, which will be sort-of a transitional release to prepare developers for the launch of the eventual QNX-based operating system.
This gives developers the time to get used to the new development environment and new operating system, which gets to mature on its own on the PlayBook and possible additional tablet devices. Some BlackBerry OS application will run on it, but it's unclear just how easily (or how many).
Good decision by RIM. Why write something from scratch when you can just buy fellow Canadian company QSS, and use their excellent and more-than-proven QNX operating system. Now let's hope that the suits at RIM are smart enough to allow us to have a (warranty-voiding) Minecraft-mode on the phone, so us geeks can meddle with QNX' internals.