At its heart, the FuelBand is little different to the UP or Fitbit; it's basically an accelerometer you wear on your wrist that tracks how active you are throughout the day, and though its understated styling and system of monitoring and achievements on your iPhone or at nikeplus.nike.com is cleverer and richer than with its competitors, the fundamental idea is the same.

That's good, because the idea works really well. Even if you make no other conscious changes to your lifestyle, just having something telling you how active you are each day is an astonishing motivator.
Tired and want to get the bus home instead of walking, for instance? Ah, but that'll probably mean you won't hit your goal for the day. It sounds almost petty, but we're yet to meet anyone with one of these monitoring devices who isn't affected in the same way.
It doesn't hurt that the Nike+ FuelBand just looks gorgeous, with its simple black rubbery exterior and single band of silver at the clasp. Press the single button on the FuelBand and a system of LEDs light up on the face; unlike pretty much every other gadget we've seen, these lights really do look as if they're embedded into the band, and the effect is mightily pleasing.
The white lights give readouts for its key metrics - number of steps taken, calories burned or NikeFuel (of which more shortly) accrued - as well as telling the time. It would be nice to have the option of keeping the time always displayed so you could glance at the FuelBand like a watch, but that would presumably have a hugely detrimental effect on the battery life; as it is, the battery can just about last a full week.
Below the white readout is a line of coloured LEDs that show you how far you are towards your goal. Having all this information live on your wrist, rather than having first to sync with your iPhone as with the UP is terrific. And unlike the Fitbit, which can only sync over a PC or Mac, the FuelBand can also sync directly with your iPhone over Bluetooth.
The iPhone app is very slick, and though the process as presented is essentially broken at the moment, the fact that you can track your activity against FuelBand-owning friends on Facebook is great.

Going for the burn

Although NikeFuel is a synthetic measure that Nike has just made up, we quickly adjusted to it; you can also measure steps and calories, but while their accuracy seems reasonable, the fact that we can't question the accuracy of NikeFuel oddly made us trust it more. Besides, NikeFuel is standardised across a huge range of Nike products, and it's a level playing field - you can 'compete' against Olympic athletes as easily as against Sandra from accounts.
As with all these things, we remain annoyed that you're on your own when it comes to setting goals. We'd like your first week, say, using the FuelBand for it to just monitor your typical activity levels, and then gently but firmly set you goals to gradually get you fitter and more active over the next few months.
As it is, we spent the first few days (when we had no real feel for NikeFuel) setting wildly generous and then impossibly stringent goals for ourselves. We feel like a bit more nannying would be beneficial as we progress; you can set goals on the Nike+ website that are bigger-picture than the usual daily goals, and it can suggest some, but we'd like it to be very much more in-your-face.
The FuelBand is easy and convenient to wear, and though some forms of exercise will be tracked less well just by the nature of the device (weightlifting, for example, or swimming, since it's water-resistant but not waterproof), it's such a pleasant system to use that you will use it.
We'd like GPS as well to track runs, say, but quite understand the technical trade-off here - it would soak up too much battery - and you could always use the separate, free Nike+ Running app on your iPhone for this.
Yes, it's maddeningly expensive, but if you can afford it - or can justify it to yourself from a pot of money you had apportioned in your head marked 'A Nice Watch' - it's a beautifully-crafted bit of kit backed up by both services online and apps, and happily complements the rest of the Nike+ range. It's just a shame that it's only on sale in five Nike Stores in London - and that, for some reason, Nike won't comment on future availability.