Will pervasive multithreading make a comeback?

exigentsky writes: "Having looked at BeOS technology, it is clear that like NeXTSTEP, it was ahead of its time. Most remarkable to me is the incredible responsiveness of the whole OS. On relatively slow hardware, BeOS could run eight movies simultaneously while still being responsive in all of its GUI controls and launching programs almost instantaneously. Today, more than ten years after BeOS's introduction, its legendary responsiveness is still unmatched. There is simply no other OS (major) that has pervasive multithreading from the lowest level up (requiring no programmer tricks). Is it likely, or at least possible that future versions of Windows or OS X could become pervasively multithreaded without creating an entirely new OS?"