Can we grade and give feedback on college essays automatically?

I am skeptical, but a New York Times article says the folks at edX will be doing just that using "artificial intelligence." They also say students will be able to improve their essays using feedback from the system. EdX promises to open the grading platform to others -- presumably as a Web service.

EdX has hired Vik Paruchuri to work on the service, which he developed for an automated essay grading contest sponsored by the Hewlett Foundation. The contest results are reported in a paper by the contest organizers, which concludes that automated essay scores correlate well with those of human readers. (Before you settle for that, read this critique of those results by MIT professor Les C. Perelman).

The Times article does not contain a link to a service and I can't find one on the edX web site, so I will remain skeptical. Grammar checking? For sure. Meaningful feedback? Show me the API or URL.