Though alluded to...
...I thought I'd put my weight behind it, too.
I have a 800Mhz G4 I use to load my old iPods with music (the 1G and 2G, as my MacBook was the ONE that doesn't have firewire...)
They work, as do a few of the newer ones, without a problem. I am running 10.4.11 though.
On top of that, I did use that as my primary computer a couple years ago when the original iPhone came out - uploading via USB 1.1 took forever and was sometimes even unreliable.
Given the information from myself and others, I'd proceed with caution on this one.
Hope that helps!