He's absolutely right. Both of them are ridiculously flawed 'standards'. OOXML because there are literally sections of the standard that don't clearly document the behavior required of the implementation (space lines according to method used by Word 5), and Open Page because it documents only the required behavior for compliant, error-free swf's, when in practice the error-handling behavior is much more important (which, if you're wondering, is why we don't have a useable open-source reference implementation of Flash - even the bits without DRM).
Gruber seems to be mocking Adobe's claim by suggesting that Microsoft Office is more open.<p>However, he never explains why Microsoft Office is not "open" and seems to be counting on generic anti-Microsoft sentiment to make the case for him. His post may have been a lot more convincing if he had explained why Office isn't "open" and then went on to explain why Flash is less "open" than Office.<p>Btw I say all this as an developer who thinks that section 3.3.1 makes a lot of sense for Apple and as someone who thinks that Flash is too buggy.
And that's the last daringfireball article I will read. I've ripped into the last three that have made it big here or on reddit and I'm tired of hearing the same things over and over.