I'm late to the debate (here, here and here amongst others) and I don't have anything very intelligent to offer, but that has never stopped me before.

It occurred to me that since Microsoft has already released a major product (Office 2007) reliant on Open XML that it doesn't matter which way the vote goes.  Open XML IS a standard.  Get over it already.  Endless arguments and debates over it's technical or political merits are pointless.  Microsoft won't be adopting some other standard any time soon - they stuck with the previous closed standard (.doc etc) for many years and only changed it when they had to / wanted to.  At the very least they are now trying to do what everone has been nagging them to do for so long.  We should be grateful!