Hey, check out this video of Sebastien Marineau, VP of engineering at QNX, as he explains how the multi-core capabilities of the QNX Neutrino OS allow the BlackBerry PlayBook to run multiple apps simultaneously:
Technically speaking, QNX Neutrino's advanced support for symmetric multiprocessing, or SMP, makes this multitasking possible. A large variety of systems, including the world's largest Internet routers, have used QNX SMP for well over a decade. Which means that the PlayBook, with its ability to deliver a full web browsing experience, uses the same technology that helps power the Web itself. Now that's pretty cool.