Yes, everyone is going ape over the Mac tablet design that has (re)surfaced. But then, people went ape over every single iteration of the iMac, the iPod and pretty much any other Apple product that kicked off (or hinted at) a new form factor, so that's only to be expected.
What people seem to be forgetting is that, if it exists at all (and if it is ever brought to market, which is the biggest issue - tablet designs or mini-PCs like the OQO are a dime a dozen) it's bound to cost more or less the same as an iBook (a little less in fact, if it's really only 8 inch wide).
Fab costs are likely to be, say, around 60-70% that of an iBook, and that's estimated mostly on parts (and heavily slanted due to the smaller screen size, which is a major factor in component costs for one of these things).
Now assuming all this, placing it at US$999 would be on top of the iBook price range.
Higher would be pointless, unless the goal was to only sell a couple of hundred.
(There is also the option of this being some sort of new "iMac Mini", which would bump up the price point significantly, but let's run with the tablet idea for a bit.)
Okay, for the sake of argument, let's make it US$799, assuming that if Apple followed a linear pricing/product placement strategy (which it often doesn't) it would have to be somewhere in between an iPod and an iBook.
Who would buy one?
Yep. That's the real question. I guess it would depend heavily on what it could do besides acting as a remote Mac display or an iTunes remote.
And I bet that, like most of Apple's modern gear, it would be squarely aimed at the home market, and integrated into the Apple "digital entertainment hub" - so no useful corporate functionality except wireless web surfing and note taking, which hardly justify even a quarter the price of a Windows Tablet PC.
So, home use would mean surfing the net, streaming music (and maybe video, if the new H.264 codec can run on it without flattening the batteries), maybe browsing iPhoto albums or (if Inkwell is good enough) sending short notes via e-mail. Paired with an Airport Express, it would be a pretty complete home entertainment system.
(By the way, the "it might also act as a phone" rumors floating around are nothing short of ridiculous. If the thing is going to act as a phone, the tablet form factor is one of the worst possible imaginable.)
Assuming it exists at all (always a nice thing to keep in mind), would you pay US$799 for a gadget that (as far as we know) has no compelling application to foster its adoption?
More to the point, I don't see myself spending that much money for yet another Apple one-off (or "classic model", as initial revisions are nearly always dubbed a few years down the road) that would most likely be either dead or obsolete in a year's time.
Now go back and think of it actually being some sort of "iMac Mini" costing even more, and you see why I'm not exactly keen on it.
Of course, if might be as wondrous as the Newton (which I would probably still use today if I had kept one), and all the points I've made above will wither away in a flood of coolness...