I'm curious to know at this time which distro supports the most hardware for the i386-64. I heard rumour a few years ago that Kanotix detected the most hardware.

I'm not even sure if kanotix is still around...I think some of their devs left and started sidux. This site shows up towards the top in google: http://www.linux-drivers.org/ that may be of some help. I generally recommend trying out the live cd versions of distros. That generally will give you an idea what is supported and what isn't.

All distributions are equal for hardware support. It depends if you are willing to find the information, download the source code, compile, and install. All distributions uses the same kernel version, but there could be some [minor] differences between one distribution and the other which are mainly proprietary patches. The patches usually improves the proprietary utilities that the distribution uses.

IMHO, Gentoo is the easiest distribution for just about any hardware because someone already figure out the steps to setup the hardware that works all the time and they made an ebuild for it.