Woo! It’s API Wednesday. The New York Times announced a couple days ago its new API, the Most Popular API, the documentation for which is available at http://developer.nytimes.com/docs/most_popular_api. The Most Popular API is for getting links and data associated with the most-frequently e-mailed, shared, and viewed NYT blog posts and content.

The Most Popular API request uses a REST format with responses in JSON, XML, and the new-to-me serialized PHP (.sphp). Essentially when building a query for this API you’re requesting three things: what you want (most e-mailed, most shared, or most viewed), which section (all sections or one or more sections) and the time period you want to include (either 1, 7, or 30 days.) I really like the share-types option, though: you can limit the “most shared” results to the method used to share the items (one or more types, with your options being Digg, e-mail, Facebook, Mixx, MySpace, Permalink, TimesPeople, Twitter, or Yahoo Buzz.) It’s be neat to slice up data and see what people are sharing on Facebook vs. Twitter vs. MySpace.

You need a key to use the Most Popular API, but NYT Open has a prototyping tool where you can experiment with the different request parameters without having to build a request or get a key. Here’s my request for the most shared-to-Facebook items for the last seven days.