For those of you who watched my PDC presentation that I posted on the other week, you probably noticed a demo where I had a document structured with controls that were bound to XML data. We did a lot of work in Word 12 to allow you to create mappings from your own XML data to content within the document. We maintain a true separation of data and presentation with this approach, and it makes programming against the data a lot easier than it was in Office 2003.
I plan to post a lot of information over the coming months on the content controls; the ability to group ranges of content; and the ability to map controls to XML nodes in your XML files. If you're curious though to see some demos of this, you can check out Tristan Davis' PDC presentation. Here is a link to the presentation: http://microsoft.sitestream.com/PDC05/OFF/OFF316.htm#nopreload=1&autostart=1
If that doesn't work you can try this (although it requires you to download all the files before it will start to play): http://microsoft.sitestream.com/PDC05/OFF/OFF316_files/Default.htm
Make sure you watch all the way through to the end, or at least the 44th minute where he gets a phone call :-)
The stuff that Tristan shows is really a great intro to the work we've done around allowing you to integrate your business data with your documents. You can see that this really builds off of the momentum we started with the customer defined schema support in Office 2003.