"The vast majority of the automotive data that powers Edmunds.com's website, iOS app, Android app and tools has been made available to the larger developer community for FREE.
This API encompasses a wide variety of vehicle-centric datasets including vehicle specs (e.g. make and model names, trim, options, colors, equipment, engine, MPG, ...etc), consumer ratings and reviews, stock photos, vehicle pricing and maintenance schedules just to name a few. The API has the biggest dataset Edmunds.com has to offer."
Edmunds Developer Portal I/O Docs (API CONSOLE), very nice!
Intel Mashery: API Management, API Gateways, Strategy Services and Developer Platform Services