Last night I had the opportunity to give a presentation on Open XML development at the monthly meeting of the Seattle .NET User Group. As promised, here's a wrap-up of the links I mentioned in the presentation:

Where to download the schemas: Office Open XML schemas (Ecmas draft version 1.3)

Where to get the .NET 3.0 System.IO.Packaging API: WinFX February CTP

Package Explorer utility:
shared source project on CodePlex
compiled copy on OpenXmlDeveloper.org

Blogs covering Open XML development:
Brian Jones
Kevin Boske
Doug Mahugh

Channel 9 videos:
Eric Faller and Savraj Dhanjal - Ribbon Extensibility in Office 2007
Generating Office Documents using the New Open XML File Formats

Other resources:
XML in Office Developer Portal (code snippets, white papers)
VSTO Developer Portal
OpenXmlDeveloper.org