Situation: .odt and .doc files correctly, open in LibreOffice Writer. .docx files on the other hand, despite having the expected LibreOffice Writer icon, are opened by "Archive Manager" by default in Ubuntu 11.10. What I expected to happen: .docx filetype would be associated with LibreOffice Writer by default and thus be opened by that program. My original report on Ubuntu's Launchpad: https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/878822
So it is Ubuntu's problem, right?