Same here.
At the college where I work, web design students and digital photography students in the graphic design department lab use g5's.
I know one freelance professional advertising designer who uses ibook exclusively. He used to have an imac also, but he sold it to me. 
I like my imac, but I would pounce on a g5 if I could afford it.
IMO, the main problem with imac is the small monitor.
When I was in the Reserves, we had a Mac with a monitor that could rotate into a vertical screen. That was great for electronic publishing because I could see the entire page full size.
