Debian has a different approach to 64-bit hardware. The entire system is 64-bit, and the only way you can run anything 32-bit is in a jail a sort of security sandbox isolated from the system itself. I suppose this adds some measure of security, but it also offers a unique experience in pure 64-bit computing.
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The Debian community once planned to make their distro a little easier to install and configure, adding the graphical installer as a first step. However, their upcoming Lenny (5.0) release candidate uses a very recent X.org package, for which virtually no Debian scripts exist. Sure, you can run the Xorg script to capture most of the hardware (Xorg -configure) and it will do just the minimum