If you are interested in a recent and solid version of KiCad we recommend to get it directly from this page. For Debian/Ubuntu/Mint/RedHat/YellowDog/Fedora Linux distributions, there is a good download/compile/install script that you can download below and run in the terminal with the command:
chmod a+x ./kicad-install.sh
You will be asked for your sudo password. This script requires 2 GB of space in your home folder ~/kicad_sources and approx 30 min, or more, of waiting. Once the script has finished you may delete the folder or keep it for future KiCad updates (via the use of the same script command). Please consider as well that various GNU Linux distro guys, the Slackware guys for instance, do maintain and distribute KiCad for their distros. If you are happy with the KiCad version that comes with your distro, go for it.
For Windows users and OS X users please refer to the proper binary package or installer/script available here.
KiCad for Windows
KiCad for Linux script
KiCad for Ubuntu via PPA
KiCad source code
Older versions of KiCad can be downloaded from the KiCad repository.
KiCad bleeding edge version
KiCad is under continuous development. For a bleeding edge version (latest & greatest version) of KiCad you should download one of Milan Horák's KiCad snapshot packages: http://kicad.nosoftware.cz/
If you find any problem with downloading and installing KiCad let us know or send an e-mail to fabrizio.tappero(at)gmail.com