I kept putting off posting this comparison because I kept changing my mind about the pros and cons of each. That statement alone should be an indication of just how differently people might relate to each of the products. That said, I've finally settled on just one of the devices and that's the Fitbit.
Obviously, the Fuelband is worn on the wrist and the Fitbit is typically clipped somewhere on the torso (bra, waistband, or my personal favorite, clipped to the top of my pocket). If you are bothered by having the tracker "out there" as it were, than this alone my be the deciding factor. Frankly, I ended up preferring the Fuelband's wrist placement. I tend to change clothes a couple of times a day. I work from home and when I'm at my desk, I figure I might as well be as comfortable as I can, so I'm usually in athletic shorts or the like, but when I leave the house, try to be a little more civilized and put on something a bit nicer. When I get home, I often change right back. So with the Fuelband, this was a non-thinker. It just hangs out there on my wrist all day long. The Fitbit had to be constantly transferred back and forth, making it much easier to forget. Still, once you've formed the habit of putting it on every time you put on pants of any kind, it's not too bad.
How you feel about each devices syncing will depend a lot on your choice of phones. If you have an iPhone, then you're set either way. Both the Fitbit and the Fuelband will sync wirelessly with the phone pretty regularly and it will almost always be up to date. If you're an Android person, as I am, then the situation isn't nearly as nice. With the Fuelband, you're just plain out of luck. There is no Andoid app. Not only that, but the only way to sync the band with the server is via a physical connection using their USB dongle.
The Fitbit has an Android app. It's not as nice as the iPhone one, but it's close. Unfortunately, the Android ecosystem hadn't settled on the low power Bluetooth standard until very recently so at the moment, there's no wireless syncing with Android phones. New Android phones like the Galaxy S III, Galaxy Note II, and Nexus 4 will be supported for wireless syncing sometime in the next few months, according to Fitbit. I'm counting the days. In the meantime, the alternative syncing method is still pretty slick. The Fitbit comes with Two USB dongles. One is a tiny little Bluetooth nub that handles syncing. You just need to be within about 20 feet of a computer that is turned on with the nub installed (and the software driver too, of course) and your data will be synced. I have the nub plugged into my work machine and I stay synced pretty much all day. The second USB dongle is for charging. You can plug this into a USB port on your computer or a wall plug adapter. Both devices have remarkable battery life and will goes many days at a time between charges.
As you can see, the convenience of syncing will vary widely from person to person, but for me and any other non-iPhone user, the Fit bit is a clear winner.
There's no contest here. The Fitbit website is infinitely more useful and comprehensive. I guess I'll discuss the interoperability factor here. Fitbit has an open API that is used by many other sites and tracking tools for cross communication, including one of my new favorite sites MyFitnessPal.com.
The Fitbit comes out ahead here as well, and in several ways. The Fitbit does sleep tracking with the included wristband and it has an altimeter for tracking flights of stairs climbed. The Fuelband does neither of these things. not only that, but as a step counter, the Fitbit was much more accurate than the Fuelband. The latter consistently under counted my steps. I checked this on several of my walks. I would looks at the step count for both devices and then take 200 steps and check again. The Fitbit was always within 2 or 3 steps of being right while the Fuelband was consistently under by 15-20 steps. This may vary greatly from person to person. Perhaps my particular movement style did not lend itself well to the Fuelbands tracking algorithms. Overall the Fitbit track more data and seems to do so more accurately than the Fuelband.
The "On the Go, How am I Doing, Motivation Factor"
This is where the Fuelband screams ahead of the Fitbit, and to such a degree that this particular advantage alone is almost enough to overcome all of the other areas where the Fitbit has the lead put together. Nike is laser focused on their activity currency called "Fuel". Sure their device measures steps, and calculates calories burned (inaccurately, unfortunately) based on your physical measurements like height and weight, but it's Fuel that is the most prominently displayed. With calories, a heaver person will burn more with each activity, but Fuel independent from such calculations. Two people who make the same movements playing basketball, for instance, should conceivably generate the same amount of Fuel, regardless of their different sizes.
So Fuel is the focus and the display on the wristband brilliantly displays your progress towards your fuel goal, and I mean "brilliant" in both the metaphoric and literal sense. When you press the button on your Fuelband, the first and main item displayed is a number representing your Fuel total for the day and underneath that is a multicolored bar that shows you in an instant how close your are to your goal. They got so many little details right here. For instance, the bar that represents your progress is topped by a single lit pixel representing your goal so that you can very easily see the unlit space between the top of the bar and the goal dot. It's a tiny usability detail that makes a huge difference.
This brightly colored Fuel count and bar is incredibly motivating throughout the day. When I'm done with my work day and I hit that button to see where I'm at, I am incredibly motivated to get out there and hit my goal. This single aspect, the focus on and activity currency like Fuel and the fantastic representation of it on the device, almost singlehandedly persuaded my to stick witht he Fuelband over the Fitbit.
The rotten thing here is that there's no reason why the Fitbit couldn't be just as effective as the Fuelband in this area. The problem is that the Fitbit folks seem to be having a really tough time thinking about their device as something other than a fancy pedometer. They are insanely "step" focused. For instance, the only way you can compare yourself to your friends is steps. That's it. Period. Nothing else. It's ridiculous. Fitbit has an "Active Score" metric on the website and I think, but I'm not sure (this uncertainty shows just how little focus they put on it) that this active score is represented by a flower on the device, but the usability and motivation factor is nowhere near as good as the Fuelband. The active score number isn't even available on the device itself. Booooo, Fitbit. Booooo! The device's display is actually pretty high resolution, albeit monochrome, when compared to the Fuelband so there's no excuse for a better representation of the active score or a more focus being put on it via the web site and mobile apps. Nike wins this round and in a big, big way.
As I mentioned above, I did finally settle on the FitBit as my everyday, all day tracker but I did so with major reservations regarding it's actual tracking metric. FitBit desperately needs to modify the device software so that it shows the activity score in as clear and concise a manner as the Fuelband does. If they do so, then I can finally declare Fitbit a no compromise winner.
As a side note, I just receive a notice from FitBit regarding their new tracker coming out in February or March. It appears to be a complement to the FitBit one as opposed to a replacement. It's a wrist worn device, but if the details I've received are correct, it looks once again that FitBit may missed the mark. This device doesn't have the full LED display of the One. It appears to have just five tiny lights that show your progress towards your goal. They dont' even mention which goal is used. Given their past missteps, I'll assume it's steps. This seems like a step back from the One. That said, if syncing works with Android (it already does with iPhone) then an on device display may indeed perhaps be redundant. They do say that Android syncing (with newer phones supporting low power Bluetooth, of course) is expected at launch. That's good news as it also likely means that we'll finally see this same functionality for the One as well.