Support for the Alpha ('alpha'), ARM ('arm') and HP PA-RISC ('hppa') architectures has been dropped from the installer. The 'arm' architecture is obsoleted by the ARM EABI ('armel') port.

The installer can be used to install the kFreeBSD instead of the Linux kernel and test the technology preview. To use this feature the appropriate installation image (or CD/DVD set) has to be used.

The bootloader that will be installed by default is grub-pc (GRUB 2).

The dialogs presented during the installation process now provide help information. Although not currently used in all dialogs, this feature would be increasingly used in future releases. This will improve the user experience during the installation process, especially for new users.

The installation system will install all recommended packages by default throughout the process except for some specific situations in which the general setting gives undesired results.

The system will automatically select for installation hardware-specific packages when they are appropriate. This is achieved through the use of discover-pkginstall from the discover package.

The installation system can be also used for the installation of previous release, such as lenny.

The installation system provides better support for installing both squeeze as well as lenny and older releases (through the use of archive.debian.org). In addition, it will also check that the selected mirror is consistent and holds the selected release.

This release of the installer supports the use of the ext4 file system and it also simplifies the creation of RAID, LVM and crypto protected partitioning systems. Support for the reiserfs file system is no longer included by default, although it can be optionally loaded.

It is now possible to load firmware package files from the installation media in addition to removable media, allowing the creation of PXE images and CDs/DVDs with included firmware packages.

Starting with Debian 6.0, non-free firmware has been moved out of main. To install Debian on hardware that needs non-free firmware, you can either provide the firmware yourself during installation or use pre-made non-free CDs/DVDs which include the firmware. See the Getting Debian section on the Debian website for more information.

Thanks to the huge efforts of translators, Debian GNU/Linux can now be installed in 67 languages. This is three more languages than in lenny. Most languages are available in both the text-based installation user interface and the graphical user interface, while some are only available in the graphical user interface.

Languages added in this release include:

Due to the lack of translation updates two languages were dropped in this release: Wolof and Welsh.

The selection of localisation-related values (language, location and locale settings) is now less interdependent and more flexible. Users will be able to customize the system to their localisation needs more easily while still make it comfortable to use for users that want to select the locale most common for the country they reside in.

Additionally, the consequences of localisation choices (such as timezone, keymap and mirror selection) are now more obvious to the user.

The installer now supports live systems in two ways. First, an installer included on live system media can use the contents of the live system in place of the regular installation of the base system. Second, the installer may now be launched while running the live system, allowing the user to do other things with the live system during the install. Both features are built into the Debian Live images offered at http://cdimage.debian.org/.