I have a suggestion for all OS X and iWork users. In Pages, Numbers and Keynote, if you open one of the programs then click, for example, 'Pages' then 'Provide Pages Feedback' it opens a form in your web browser to provide feedback to Apple.
I'm suggesting that if everyone who uses iWork and supports open standards were to provide this feedback to Apple, they may not immediately jump and implement ODF support in the next iWork but they'll sure know that a lot of people would like it and hopefully they would take our opinions seriously.
Keep promoting ODF people,
edit: if you don't use iWork then you can get the feedback page here: http://www.apple.com/feedback/pages.html , maybe just tell them you would be more interested in the iWork suite if it supported open standards?