What? So the iMac was done to use Safari, iTunes and a bit iMovie. I guess professional but not hardcore Photoshop an iMac is just perfect. But I agree that the iMac should get real hardware soon or it will be quite outdated.
You can still do photoshop on an iMac with integrated graphics, and it will still be super speedy, but it won't have that extra few percent of extra speed from GPU processing that only a graphics professional would even notice was there.