It appears that Microsoft has now provided 662 responses to the ISO comments on DIS29500 (Office Open XML) through Ecma, but those responses are presently only available to members of the ISO voting organizations through password-protected access. This move is already gathering much criticism from the ODF camp.
Guess what: those responses are neither provided in ODF format nor in OOXML. They are 662 individual PDF files. How ironic is that...?