As much as I like Nokia hardware (and I do) I fear the OS horse has firmly left the stable and has galloped across the galaxy - six times in fact.
It would be pointless releasing an Android phone and competing for scraps against the likes of Samsung. Equally, releasing a competing OS when the ecosystem is with Android and Apple would seem pointless. Maybe they can port apps as Sailfish purports to do, but then the hardware would have to be out of this galaxy to win.
If only they hadn't f*cked up with Meego. Nokia only have themselves to blame - they foresaw the future, then f*cked it all up.