I don't know whether or not to laugh or cry at some of these comments.
For those that haven't figured out Apple's strategy yet, they're a business and their goal is to make money, and they seem to be doing a pretty good job at it.
One of the ways they do this is their product parts cycle. Right now they've got a pretty good line from the MBP down to the mini using all laptop components. Even looking at the new keyboard you can see this parts reuse strategy. It's easy to see that the next MB's will get the guts of the current MBP. The next mini will get the guts of the current MB. The iMac kind of fits inbetween the MBP and the MB. This all reduces their overall costs. The MacPro is kind of on it's own, and that's why there's a larger premium on it.
So, the mini is there for the last of the line, left over parts. But they're still selling it a decent premium, and they'll keep selling it until they run out of parts more or less. They really do sell, despite what people here might think.
Just think of all those people saying, well, the

tv doesn't quite do everything I want it to do. What do people tell them? Buy a mini!
For all those people saying, well, the mini doesn't quite do everything I want it to do, I think I'll get an iMac or a MB.
For all those people saying, well, the iMac or MB doesn't have the ooomph I really need, then get a MBP or a MP.
So you have

tv -> $299 and $399
MacMini -> $599 and $799
consumer (all in ones) -> $1099, $1199, $1299, $1499, and $1799
Pro -> $1999, $2499, $2799
See what they're doing? They keep bumping you up the line. Eventually everybody has their limit, but their goal is to squeeze the absolute most out of you. Ideally everybody would have a fully stocked MacPro with 2x30in ACD's.
As long as Apple has something like the mini to get people to look at their computers, its easier to upsell them on something better. They just need that $599 price tag to at least be there for people that normally would only be looking in that price range. Plus, it's a great way to get the last bit of money out of their older parts AND it really is a great machine that a lot of people have put to varying and interesting applications.