Lst's face it...
....it's just not going to happen is it? Microsoft absolutely will not support any kind of standard that anyone else does and (of course) those that it does, it "extends" with features nobody else actually wants, whether it be file formats, network protocols, you name it.
eg - They have their own version of the "standard" kerberos. Their "standard" (and pretty shit-poor) firewall authentication protocol (ntlm) is "standard" only to MS (the only reason anyone else supports it is because they HAVE to, not because they WANT to). They have their own email access standard (Outlook) which is a law unto itself and plays very badly with the network at large, they have their own idea of what HTML and CSS is, they have custom file formats that nobody else can understand, they invented that truly ugly abortion called "the registry",
MS should be banned from any involvement whatsoever in ODF specification development. What possible reason could their be for allowing them in? They have publicly stated that they don;t like it, don;t want it and have come up with a cruddy alternative OOXML who's only purpose is to be different (surely nobody seriously thinks OOXML is anything other than an expensive diversion to lure stupid business users away from ODF?). With this background, why the hell would you want them to have any further involvement in ODF? It's dancing with the devil!
As for "...Open XML [is] no longer exclusively a Redmond specification".
Maybe not, but this nobody else actually wants the bloody thing!