OK, so what's the general impression of the Intel iMacs?

[Silencio]

I have two 20" iMac Core Duos set up for a client now. They don't do anything heavy duty -- mostly Office 2004 and Filemaker work, with a little iApp action in between. No complaints about performance, really.

The only real stress tests I tried were extracting a DVD with MacTheRipper and re-encoding/burning it with Toast, and both of those took significantly longer than on my Dual G5 at home.