I still get folks asking me questions about the licensing of the Open XML formats from time to time, and it seems there is a lot of misinformation out there. It's actually been well over 7 months since we made the move away from licensing the formats and instead just provided a general commitment to not enforce any IP behind the formats. The legal term for this new commitment is CNS (covenant not to sue). This allows anyone to develop against our formats without having to worry about patents, and this it's irrevocable (meaning it can't be changed in the future).
The CNS is available up here (http://www.microsoft.com/office/xml/covenant.mspx). Recently we took an additional step to help people who don't want to deal with parsing legal documents, and actually asked an outside law firm (Baker & McKenzie) to do a study for us on both the standardization as well as the CNS. I think any of you folks who've been frightened by some of the FUD that has been spread about the Ecma Office Open XML formats should take a look: (Link)
Some good takeaways I wanted to call out were:
Have a great weekend everyone!
-Brian