A quick update for Ubuntu 11.04 users: LibreOffice 3.4.3 is finally available in its official PPA. For what's new in LibreOffice 3.4, see THIS page.
The LibreOffice PPA also provides the latest LibreOffice 3.4.3 language packs as well as an updated LibreOffice AppMenu (global menu) extension that should work with the latest LibreOffice 3.4.3.
To upgrade to the latest LibreOffice 3.4.3 in Ubuntu 11.04 Natty Narwhal, use the following commands:
sudo add-apt-repository ppa:libreoffice/ppa
sudo apt-get update
sudo apt-get upgrade
via Le Libriste (in French)