The Rdio iOS SDK by Rdio allows API interaction via a native playback implementation. With the SDK, developers can make calls, authenticate users, and stream audio. Available framework, documentation, and a getting started guide.
Music video content provider MTV recently announced that its Content API is out of private beta and available to the general public. Available as part of a new MTV Networks Developers Tools web site, the RESTful API gives access to content from MTV, VH1, CMT and Logo. The API supports a variety of open standards including OpenSearch and MediaRSS for data results (see our new MTV API profile for more details).
Last.fm besides being one of the most popular online radio and music communities, also has one of the most popular online music APIs. Possibly the most popular. Each month we continue to see a variety of new music-themed mashups added to our directory built on the Last.fm API. In the first three weeks of this month alone there have been 5 more Last.fm mashups added. That means that out of 231 music mashups at least 84 use the Last.fm API. And not that developers don't have other options given that there are 44 music APIs to choose from.
In our writeup on Seevl, we mentioned that using the Seevl API to add context to Youtube videos would be ideal. Well, apparently, it was thinking along exactly those same lines. I talked briefly with Alexandre Passant, who is one of the main people at Seevl, and we talked about the company's new mashup, and its future plans for the API.