This feels important to me, and was exactly the kind of thing that got me all excited when Jean Paoli first showed me this stuff way back when. I can think of all sorts of applications where the ability to generate a Word doc on the fly is going to be real useful. A lot of parts of the world still run on paper, and Word is a pretty good way to generate it.
Two comments: First, I think there are going to be lots of easier ways to do this than the way Oleg did with XSLT. Second, his first prove-it-works doc contained the text “Hello Word!” Now that's funny.