As for why we need autonomous cars, check out the technology Lexus is working on (and, has already implemented). Pretty damn amazing!
Their rationale for autonomous vehicles is to allow the older generation to still enjoy getting on the road and going for a drive.
I originally saw the article in a Wheels magazine a couple of months back while waiting for a pizza, but, here's a web version:
http://www.theverge.com/2013/1/7/384...g-car-ces-2013
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