This looks great. I'm building http://dokket.aws.af.cm. It's a database filled with documents from the Federal Communications Commission. From day 1, I've been looking for smart ways to make use of the thousands of documents of unstructured text. The customization you offer seems to be the killer feature for me.

I'll write a Ruby api wrapper if you give me an agreed-upon amount of usage when you settle on pricing.

Feel free to email me (HN name @ gmail) if you're interested or just want to follow up for customer development purposes.

Best of luck!