LibreOffice 4.1 comes with many changes, including Unity appmenu support, option to use Firefox Personas, better interoperability with DOCX and RTF documents, a new LibreOffice Impress Remote Android App and many other changes
LibreOffice can be installed in Ubuntu by using a a large archive of deb files that can be downloaded from LibreOffice.org, but the packages available in the PPA (or in the official repositories) come with some Ubuntu-specific tweaks – for instance, the LibreOffice debs downloaded from the LibreOffice website didn’t have built-in Ubuntu appmenu (global menu) support, at least in my test, while the packages in the PPA have this by default, even for Ubuntu 12.04. Another advantage of using a PPA is getting automatic updates / easier to upgrade to newer LibreOffice versions.
sudo add-apt-repository ppa:libreoffice/libreoffice-4-1 sudo apt-get update sudo apt-get upgrade sudo apt-get dist-upgrade
Now you have Libreoffice 4.1.