You can get Mini-ITX systems with regular processors. Heat dissipation is more of an issue of course. And if you run a decent distro you won't have the dumass RedHat `everyone has a PIII' assumption built in.
I think the true value of these things is as a sort of modern version of X-Terminals; put a CompactFlash IDE converter in them, and boot them off a 32MB CF card, and you've got a workstation with no moving parts, and no configuration! Which means 10 year+ longevity and nice silent operation. Because the CF card is removable, IT can easily get systems working again by simply replacing the CF card, then taking the failed one back and re-imaging it.
Just out of curiosity, will the graphics card (that's the Trident Blade, isn't it?) go to higher resolutions at a lower colour depth?