This image release contains updated packages from the previous ev3dev-jessie-2015-05-20 release, including packages from the Debian 8.1 point release and a new ev3dev kernel.
Note: If you have already installed the ev3dev-jessie-2015-05-01 or newer release, you
don’t need to install this new release.
sudo apt-get update; sudo apt-get upgrade; sudo apt-get dist-upgrade
is (hopefully) sufficient to get all of the changes. If you have an older release,
you need to install a new image because of some major changes.