http://en.wikipedia.org/wiki/Li-Fi, http://www.lificonsortium.org
Using light to transmit data makes a lot of sense.
http://www.wired.co.uk/news/archive/2013-11/05/chi-nan-li-fi
However, Wi-Fi still has its advantages.
http://www.bbc.co.uk/news/technology-24579776
http://gadgets.ndtv.com/internet/news/li-fi-scientists-achieve-10gbps-data-transfer-speeds-using-leds-439409
http://www.pcworld.com/article/2060921/chinese-professor-builds-lifi-system-with-retail-parts.html
http://www.howstuffworks.com/wireless-network.htm
https://itunes.apple.com/ca/app/skype-wifi/id444529922
It just wasn't possible until the Internet was fully up & running.
http://paleofuture.gizmodo.com/the-internets-save-the-date-a-tiny-item-in-a-ucla-stu-898064971
Too bad there wasn't a public Internet back in the 1970s or at lest by the 1980s.