I am proud to announce that we have released 2 new SDKs related to XMP in the XMP Developer Center.
The first is the XMP Toolkit 4.4 which is available under a BSD license and includes support for new file formats: ASF (WMA, WMV), FLV; MPEG4; SWF; and folder-based video formats AVCHD, P2, SonyHDV, and XDCAM.
The second SDK is the FileInfo SDK that documents how to customize the metadata UI across the CS4 applications. Since the CS4 metadata UI is based on Flex, it provides the ability to connect to web services and use custom Flash based UIs.
We have also provided a 3 part specification that clearly outlines the XMP data model and serialization methods, standard schemas that are support in Adobe products, and importantly how XMP packets are stored in various file formats.