Ask HN: What's missing from government data APIs?

There seems to be a lack of centralized data available over an API. GovTrack does a very admirable job, but doesn't provide data in JSON formats, and has recently deprecated its congressional member API without a replacement. The New York times has decent APIs, but districts are only available for New York state.

A decent, modern, fully featured government data api (including state and local data) could be a real boon to social good, but would anyone use it?