... is not $500/month. Don't be fooled.
To lease a Model S, the deal is something like 10% down, and a residual value percentage equal to a Mercedes. Federal/State incentives go to Tesla.
A monthly payment on the 60kW Model S will cost around $1100. Then, to get you down to $500/month, they pretend gas costs $5/gallon, and factor in a business tax deduction!
Then they offer to factor in saved time from not buying gasoline, and saving time by riding in HOV lanes in California.
Drop the business tax deduction, assume gas costs $4/gallon, and ignore the HOV lane time savings trick, and I get a monthly "equivalent" lease cost of $914.
I can't believe the press is lapping this up without doing 10 minutes of research.
Try it here: http://www.teslamotors.com/true-cost-of-ownership