Music notation modeling is entering the new multimedia Internet age. In this era new interactive applications are appearing on the market, such as software tools for music tuition and distance learning, for showing historical perspective of music pieces, for musical content fruition in libraries, etc. For these innovative applications several aspects have to be integrated with the model of music notation and several new functionalities have to be implemented, such as automatic formatting, music notation navigation, synchronization of music notation with real audio, etc. In this chapter, the WEDELMUSIC XML format for multimedia music applications of music notation is presented. It includes a music notation format in XML and a format for modeling multimedia element, their relationships and synchronization with a support for digital right management (DRM). In addition, a comparison of this new model with the most important and emerging models is reported. The taxonomy used can be useful for assessing and comparing suitability of music notation models and format for their adoption in new emerging applications and for their usage in classical music editors.