Blogcatalog have just launched an API for programmers giving extensive access to the data contained within both the user profiles and blog profiles.
The BlogCatalog REST (REpresentational State Transfer) API allows the retrieval of public user and blog data based on a set of input parameters. This page outlines the various types of requests that can be executed and provides example requests and responses.
I had a play around with it early today for the first time and a couple of bugs were cleaned up since then and I think developers will find the terms of use fairly unrestricted.
I have actually
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