Well, the good news for these guys is that if Apple does come down on them, all they need to do is remove any mention of Apple or Leopard from their product, market their machine as "Compatable with All Operating Systens", and there'll be NOTHING Apple can do.
Just because these guys are selling a computer that will run Leopard with minimal hassle doesn't mean Apple has any case. The only thing they could get in trouble for is allowing the buyer to have them install OS X.
I for one love this idea. If I didn't already have the ability to build my own system that runs better and is cheaper than any Mac on the market, I'd take a look at this. At the very least, this will be good for people to look at to see what kind of hardware that they could use to build their own Hackintosh.
Also, if Apple wasn't so stupid not to have a headless iMac with some upgradable components like a video card, this type of thing wouldn't be such a big deal. Clearly the interest in this shows that such a product would do very well in Apple's lineup. Until then, Apple will continue to apply the RDF over everyone into thinking that their Desktops are worth the money.
You can't really compare a bunch of component costs to the price of a complete machine.
Go to Dell and configure a similar spec machine to the Mac Pro and you'll see just how competitive the Macs are
Except that not everyone wants such a pimped out system. Some of us would like a lower cost, less spec'd machine with the ability to upgrade video and an extra PCI card or two. Apple provides nothing of the sort at a more reasonable price for those of us who don't drive a BMW.
I hate when people tell you to configure a Dell system with similar specs and realize they are the same as a Mac. What's the first thing you have to do when you visit Dell's configuration page? You have to pump all the Specs up to match the price and features of the Mac Pro. The problem with Apple is that you have no other options. Dells you have plenty of "lower featured" options and can still get a usable system.