TerraSoft Solutions, the guys who bring Yellow Dog Linux to the PPC platform, has stated that it will update Yellow Dog Linux (YDL) so it can run on the new PowerMac G5! They also said they are taking pre-orders for PowerMacs with both Mac OS X and YDL pre-installed. That’s what I would order if I were to get a new G5.
I use YDL on my Pismo Powerbook, and it runs smoothly. I can’t imagine what it would be like on a new G5.