SP1 for Office 2007 is now available for download. One of the interesting fixes we made was based on some problems we found when you tried to use the ODF translator that Sun has built for Office. Malte Timmermann pointed out on his blog back in the summer that there were some major issues when you tried to run their translators on Office 2007: http://blogs.sun.com/malte/entry/more_details_about_sun_s
I had some folks look into it a bit, and it turned out there was a bug where we assumed any file that used ZIP as its container format was an Open XML file (even if it was an ODF file). This meant the ODF file would fail to open as it never was handed off to the translator. Thankfully Malte pointed this out and we were able to make some changes that have fixed the problem.
Today Malte says that he's had a chance to download SP1, and everything is working, so that's great news: http://blogs.sun.com/malte/entry/sun_odf_plugin_1_11
If you haven't tried out their translators yet, give them a try (download SP1 first). They took a different approach from the other ODF translator project that's up on sourceforge.