This simple org file:
 * This is a list
 * Here's another item

produces the simple-list.odt file attached with the latest org-mode (from
git master).  MS Word 2007 (10.0.6683.5002) SP3 can't open it; it says the
file cannot be opened because there are problems with it, then says it's
corrupt.  It then offers to recover the contents of the document; that
works and it comes in fine.  This is on Windows 7.

I don't have OpenOffice on this machine so can't check it there.

(This is not a big problem for me, but just wanted to let you know.)

-- 
Gary