The biggest pile of poo you could imagine !
I wrote to the UK representative (BSI Chair) and asked them specifically to object to the fast tracking application as a blatant and absurd abuse of the system. I also asked that they refuse the whole application on the grounds that it sucks - though not in those words !
The document is 6000 pages, yes a whole SIX THOUSAND pages, which means that as was pointed out, someone would have to read and digest 200 pages/day to review it in the 30 days allowed for the fast track process.
It wouldn't be too bad if it was actually a decent standard, but it's yet another of those non-standard-standards things that would allow Microsoft to tick the "standards compliant" box whilst actually providing a grand total of ZERO interoperability. For example, the standard allows for objects to be included which are defined as "the format handled by program X" (for example Word 95) - and since the formats are proprietry and closed, it means that an "open" document is no more open than any of the previous closed docuemnt formats, it simply wraps up a proprietry format in an open wrapper.
Then there's the page stuffing stupid things like ... There is an ISO standard for country and language codes, so Microsoft ignore it and create their own. There is an ISO standard for dates and times, so Microsoft ignore it and create their own. What is worse, the standard mandates the faulty implementation of leap years so as to maintain backwards bug compatibility with that old Excel bug !
No, there is very little going for this standard, it is nothing more than a blatant attempt to maintain the current situation of proprietry formats and vendor locking - but with the added bonus of "ticking the standards boxes".
If you want a point by point breakdown of what's wrong with it, try http://www.grokdoc.net/index.php/EOOXML_objections