"OpenOffice.org goes a little further than Microsoft in
some places and allows users to export directly to PDF. It also has
its own file format, ODF, which Microsoft has pledged to support.
"While OpenOffice.org supports macros, macros written for
Microsoft Office won't work in OpenOffice.org, and can't be
transferred, which could serve as a major stumbling block for those
looking to migrate, depending on how much effort has been placed
into writing macros. You'll have to rewrite them all""