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Research Firm Claims Most cars still cost more to charge than to fill up with gas
(www.businessinsider.com)
This is a most excellent place for technology news and articles.
This is definitely hitting the nail on the head. Until the technology trickles down into the lower-end models, it's not anywhere near as much a cost savings when you have to buy way up in trim level to get electric as an option.
It's also worth noting that electric economy is notably worse in cold climates - your internal combustion car generates heat for ~free, the electric heater in your Tesla does draw a fair bit of current.