There is one particular aspect of Microsoft's document format going through ISO process that I had a hard time to find a counter-argument against: "Well it is better to have multiple open formats, isn't it?". Last night when I was presenting in a Document Freedom Day event, I finally got one. When multiple standards exist in the same area, two options can exist:
What Microsoft proposes is much worse than the power plug mess, because the power plug standards are at least restricted by region. But imagine going to another country and having to be ready that you hotel could have any one of 8 power plug types at random. And while electricity is rather easy to convert looselesly, complex documents are far more .. complex. It is like having to buy 8 different power bricks for each of your electrical devices to be prepared for all possible voltages, frequencies, waveforms, polarities and whatnot.
Having more than one ISO document standard in a horrifying idea for any programmer that will have to ever work on software that will need to support both of them - twice the work for no etra benefit whatsoever.
If Microsoft can prove (in technical terms) that their file formats present capabilities that Open Document can not, then the only sane way to implement those in the ISO format is to add those capabilities as an extension of the existing Open Document format and not to reinvent the wheel.
Microsoft also has a habit of pointing to JPEG and PNG being "competing". Well, they are not - those are complimentary standards, because JPEG is designed for compression of photographic details while PNG is designed for the compression of bitmapped vector images. Something like DejaVu could be seen as a superset of the two formats.
So, if you ever need an argument against more standards - remember about the power plugs.