Open Document Format is truly picking up steam. I expect this to continue, but not in the landslide fashion many others predict. It will be a slow and steady growth.
Microsoft wants their XML format to be a standard, as well. It won't happen unless MS takes steps to commit their copyrights irrevocably to the public, all of the public and at NO charge. RAND (Reasonable And Non-Discriminatory) licensing won't cut it with the standards organizations. They show no indication of giving ground on this point, though they may, eventually, come around. In order to get in on the rush, they can't wait too long.
By the way; Given my druthers, I'd choose the MS formula over ODF. It's a bit more capable, in my opinion. But there's no way I'll go back to Microsoft Office as my primary productivity tool kit. The price is simply too high for me.