To counter the potentially Dyson oriented review above, I am a non Dyson employee but a complete sucker for anything weird and wonderful:
And yes, the Dyson air multiplier is indeed incredibly weird and rather wonderful!
In a nutshell: Noisy as hell/ Beautiful design/ Effective air cooling/ Gadget freaks dream.
In more depth:
To take its basic function - a fan/ air cooler - its performance is, as you would expect from Dyson - remarkable. Ive no idea how it properly works but it does, and is akin to having a window open on its lowest setting. On its highest, its like standing outside on a breezy day (it wont blow your cheeks out but it will certainly have your hair horizontal). In short - it would work well in most sized rooms.
The breeze from it is very cooling, even in a warm room, so to cool you at your desk it is brilliant.
It pulls air through its base, and blows this over an aeroplane style circular wing. Its very clever, and produces a soft, smooth stream of air (though to be honest Ive never been uncomofrtably "buffeted" by a standard fan, but whatever).
The noise however is borderline obscene! On its quietest setting its a little louder than a standard PC fan - again, not a problem on a desk or in a conservatory, but it would likely keep you from falling asleep and certainly score problems watching TV. On its loudest setting it sounds somewhere between a hairdryer and a cooker extractor on a low setting. For a fan - startlingly loud in other words.
So essentially - the noise tollerance is personal: I could get used to the noise at lowest setting, but never at any other level - I was dissapointed with how loud it was (its much MUCH louder than a normal desk fan or air con unit) hence it dropped a star.
The design though is exquisite. The finish is soft grey in complimentary detail shades, its plastic is similar to that of a dyson cleaner (its not thick or shiny, its matte and very light, so easy to move around) and in terms of over all looks, its a real man-fan, and certainly gets people talking. The base unit as it revolves does so fully from top to bottom, so it looks really cool and clever, and the power button (flush with the unit so very nice styling) has a soft blue LED behind it which fits nicely to the design.
Controls are simple and intuitive, as is set up (it arrives in two parts, the large circular "wing" is slotted and clicked into place easily), and the tilt function is really tactile and simple.
As touched on, its a very masculine looking product, though not exclusively so, and as it has no blades is indeed very safe (I proved this by putting my head through it, as you do). Im not sure how much an issue safety really is though, as most fans have a fine mesh guard on.... so....
Worthy of its £200 price tag?... I really dont think so now; I would happily pay maybe as much as £150 for it, purely for its tech appeal, and it really looks stunning on my desk (everything is grey, black, silver shades and it fits in beautifully) but the noise level really does make it's price tag a bit insulting.
If you are a tech head, design freak or gadget monster, then its definitely one of the more impressive toys you should ask for for christmas, but I would suggest you wait til the price drops or you can get it on sale.