I am running a g3 700 MHZ iBook and bought iLife '04 right away because of GarageBand. I was at the MacWorld conference when it was announced and asked whether or not my computer would be able to run the software. They told me the minimum requirements were a g3 600 MHZ. They didn't, however, say that I wouldn't be able to use the software instruments (which is precisely what I needed) unless I had a g4. Does anyone know if there is any way I will be able to run the software instruments on my Mac?