$10,000 for 10 miles a day of electric driving is a pretty steep price.
If I drove it 10 miles on e-power every day, that would be 3650 miles a year or 36500 in 10 years. Since the Prius ges good gas mileage, figure 45, that would save me 811 gallons of gasoline (over the 10 years), at $5 a gallon I'd save about $4,000.
I'm not anti-Prius or someone who thinks the Leaf is the answer for everyone, but I would think thjey would have to have a bit more range and a premium of no more than $5,000 to make this work. I'd love to see dozens of electric and plug-ins on the market in the next few years.
And, if they are running three 3kWh battery packs, that shouldn't cost Toyota more than $4000 (based on rumored cost that Nissan has been able to source the batteries at under $500 per kWh). And that would be reduced by whatever the NiMH battery pack costs that won't be installed-- so they could make this work if they can lower the price. And maybe they will!