Comment Re:I wonder how long... (Score 3, Insightful) 50
Well, they're already opting to have damaged natural joints like hips and knees replaced. That's a case of upgrading from natural to artificial to gain function. As the performance of artificial limbs increase, it might become an increasingly commonplace treatment for older people, just like knee or hip replacement.
If we project that trend forward for twenty or thirty years I wouldn't be surprised at all to see artificial legs that outperform natural legs for the purposes of walking or even running. But I don't think people with normal abilities will be trading in their limbs just to be able walk a little longer, run a little faster, or carry more weight. That won't happen until the replacement is subjectively indistinguishable from the real thing; until you can feel the grass under your toes.
I'm comfortable predicting locomotion parity in the next fifty years, but I wouldn't care to speculate on when we'll see sensory parity.