Hey:

This could be useful to look at http://ubuntustudio.com/wiki/index.php/Welcome%2C_Musicians%21

Yup, check that site out. I have Ubuntu breezy and OSX running on my powerbook and was able to follow the instructions at the ubuntustudio.com site to get a nice low-latency kernel and good pd performance. Only problem from a newbie perspective was the fact that it did require patching and compiling the kernel, but the instructions would probably be pretty clear to anyone with a reasonable grasp of the command-line.

The audio performance is excellent... PD runs about twice as fast as it does on OSX. The only hardware problem is that the built-in microphone is not recognized (which I don't really consider that big of a problem ;-) )

Warning: Gem and pdp will be most likely be extremely slow on any ppc linux. AFAIK ATI's proprietary drivers do not support any of their apple video cards. Perhaps someone knows of a work-around but I just stick to OSX for video work.

However have you considered using http://www.demudi.org/ ?

unfortunately demudi is x86 only.

...happiness equals freedom equals personalities!