OOXML Debate - Something I don't get....

I was wondering whether or not anyone can shed some light on the OOXML controversy for me. Specifically, why are many people against Microsoft's submission to the ISO? It seems to me that, standardized or not, no company really HAS to support it unless they choose to. I see what Microsoft has to gain (ISO Standards might well be required in some businesses), but why are so many people against standardization? Especially when standardization opens up the format, legally, for many developers?

The only reason I can think of is basically one that supports the ABM crowd. You know... "WINDOZE IS 4 TEH SUXORS... OMG ROFL!!!111!!!"

There has GOT to be something more to it than that. I can kind of see a company like IBM against it: they have competing products and it's their job to make things as hard as the competition as possible. But many of the open-standards crowd should be behind it..

What don't I get??