I'm here because I'm trying to install it on a USB stick to try out. I have tried the live CD for 12.04 Precise Pangolin I bought off eBay seller on my PowerBook. The OS looks really nice on my 17" G4 1.33 w/1gb ram and I believe it will suit your needs very well also. It is best to try the live CD first and see how the hardware runs, but you probably know the CD file system is slow. I have run Ubuntu on Intel PC with similar configuration and it was very snappy. I recommend backing up your machine and be sure you can restore it from cold, hard metal before you do.
{I am hesitant to monkey around with my OSX 10.5.8 partition (no original Apple CDs) and made a small boot partition on a 32GB USB stick, but the installer puts all the files on the Linux partition of 25GB on the USB and then crashes because I made a 3gb boot partition on the USB to keep from modifying my hard disk. I will hopefully get that sorted later - I think I just need to prepare the boot partition with the Mac OS first. This seems the best way to go to run on the hardware before committing to re-partition my drive.}
Just my opinion, of course. I am trying to keep my OS intact because I like all the Mac OSX programs, but want a more secure web experience (since no modern browser seems to support the PPC anymore on OSX) so I just want to run the web from the USB, and I intend to strip a lot out of the Ubuntu I won't need. If you find you don't need the OSX any more, then go for it if you are sure if you can back out later.