Open XML SDK V2. The first CTP of V2 of the Open XML SDK is now available for download.

This release includes a high-level DOM (document object model) for Open XML development, as well as several tools to streamline Open XML development:

• The OpenXmlDiff utility identifies differences in the markup in two Open XML documents.
• The Open XML Class Explorer helps you determine which strongly typed class to use for a specific task, and includes the text of the relevant section of the ECMA-376 spec for each class.
• The Open XML Document Reflector takes a target document as input, and with a few clicks it shows you the C# code needed to generate that document (or a section of it) with the Open XML SDK.

See Eric White's blog post for more details.