The 7digital Android SDK by 7digital allows developers to integrate the 7digital API's preview streams, music charts, music metadata, search, and purchasing into their Java-language Android applications.
Peachnote is quite an innovative approach to music analysis. Developed by Vladimir Viro, a renaissance man who bridges the worlds of classical music and advanced mathematics, the Peachnote API provides the ability to search a large collection of public compositions by melody or sequence of chords.
Yahoo has just released a cool new embeddable media player, Yahoo WebPlayer, that supports MP3 and WMA files, as well as multiple services like YouTube and Yahoo Video. Yahoo has also launched a whole new site to attract publishers and developers and to encourage them to use the player when publishing audio and video across the Web.