As for the design and some people's comments... They do say they're aiming at the female market, who they feel are increasingly deciding high-price purchases; they are talking high-end market here. This is also why they "pimp" it out like jewellery. There's precedence for the colour schemes for computers; think original iMac. They were huge sellers in their time. They were probably inspired by Mobiles (cellphones) as well, like the Nokias with their interchangeable face plates. People love to personalise their treasured tech-toys. Let them.
The "Metro" could also be for the "Metrosexual" market.
The e-ink cover would be a great feature; it's been though of before, but I don't think applied to a production notebook before. Lots of mobiles have external screens. E-ink uses little power.
The thin design and battery life is primarily due to the lack of a hard drive, and possibly a CD-drive, much as what Apple has been experimenting with internally, and no doubt other manufacturers, Flash-based units have been thought of before, the issue being size and price compared to HDs. The runaway success of the Flash-based iPod has had a lot to do with driving down the price of Flash memory and increasing sizes to the point where they are starting to become competitive to some hard drives, even for a notebook like this. There are no specs, so we don't know how big the storage is. Plus price was no issue in this prototype.
There is one precedent of a notebook with Flash-based storage instead of a HD: The $100 children's Machine for the 3rd world. As it is handcrank-powered, things like CD-drives and HDs were excluded, relegated to external devices at the school where the children will go.
It seems very probably that Apple has similar prototypes in their labs, judging by their patents and other hints. Hopefully the changeable colour covers will inspire Apple to think back to their first great hit in the Jobs-led revival. Similarly I hope they investigate the E-ink covers. Comparisons to the iPhone are hardly relevant, as they have different uses. Some things overlap for which the iPhone, among others, may be more suitable, but a laptop is far more versatile, beyond playing Solitaire when bored on a bus or plane. You can't write long letters or essay on a mobile, for instance.
As for the Magnesium: That should be right up Steve-o's alley. His baby, the NeXT cube, was made of black Magnesium alloy. and no, it wasn't flammable. There's a great story out on the Net in the form of a letter from an ex-NeXT Magazine employee to his boss, explaining how he came to destroy his boss' NeXT cube cover. For an issue detailing the demise of the Cube, they wanted a picture of a burning NeXT cube. Since it was Magnesium, they figured it wouldn't be that hard. It's a long detailed story, they had to go to a special government facility where they were authorised to burn toxic materials at high temperatures. It turned out to be extremely difficult, as the alloy had flame-retardant materials in it, and when they finally managed to destroy their primary Cube case, it was not spectacular enough for a cover. So the backup, being the boss' case, was used. After a long time, they finally managed to get a good flame when exposed to extreme heat, and they got their cover.
Also please note no mention of OS or manufacturer was made. They could just as well be working with Apple, though considering the latter's secrecy, Intel probably wouldn't have been allowed to show prototypes if that was the case. But Intel might be shopping around, and this is one way to get Apple to sign up; We're going to give this design to a PC manufacturer if you're not interested.