Last year, when I was socializing the idea of creating the OASIS ODF Interoperability and Conformance TC, I gave a presentation I called "ODF Interoperability: The Price of Success". The observation was that standards that fail never need to deal with interoperability. The creation of test suites, convening of multi-vendor interoperability workshops and plugfests is a sign of a successful standard, one which is implemented by many vendors, one which is adopted by many users, one which has vendor-neutral venues for testing implementations and iteratively refining the standard itself.