Well, let's get back to the rumour then. Whether that box is a fake or not does not deny that there's the rumour of a 'cheap' (499 or 599 USD) headless Mac around. And I personally think it won't be a 'media centre' device but rather a 'normal' low-end Mac. Nothing fancy with video. Sure, you can still hook it up to your TV or video beamer - but then again you can also do that with a PowerMac or an iBook. The difference may be that this device _fits_ your home system better, because it _is_ a slim desktop after all.
I think it's simply the device that'll bring over many more switchers and - even more importantly - those who think they'll keep their PC and add such a cheap Mac to the arsenal - only to find themselves buying a 'real' Mac when the time comes around to upgrade either the PC or the Mac and get rid of one system totally...
But also think about business... Put twenty of those with MS Office plus an Xserve into a building, and suddenly you can think less about viri, system updates etc. Plus: They're cheeeeeeeeeeeeeeeeap!