We are preparing a minor update to the OpenType spec that will appear soon. For the most part, this will provide clarifications or correction of errors in describing the new table formats used for variations. Some of these may have impact for tool or platform implementations that are in progress if people didn't see past the errors or ambiguities to see the intended design.
There will be one noteworthy design change, though: The version 1.0 STAT table header will get an additional field at the end of the header, "elidedFallbackNameID" (a USHORT). As we worked on implementing support for the STAT table, we noticed that there would be cases, when using the STAT table to generate family and sumfamiy names mapped into legacy font models, that a subfamily string would have only elidable descriptors, leading to an empty string. The elidedFallbackName field allows font developers to specify a fallback subfamily name for use in such situations.