It really depends on what you're trying to achieve for yourself physically. If you want a little motivation to get going, I think it does a good enough job. However, if you're really in *need* of motivation, then there lies a bigger problem - which would be that you just don't have a desire deep inside to be physically active.
I have two friends who have fuel bands. One encouraged the other and the 2nd friend got it out of excitement. 2 weeks later (with me asking for daily and constant fuel checks), he eventually stopped responding and haven't heard or seen a pic of his fuel points since. My friend Dan who originally had it first is about to hit 100 days straight, but his daily goal is 3K. Sure it's a great feeling to hit that daily goal and I'm sure it feels good to reach it everyday but so can people who set their daily goals to 1K.
Example, for my one friend who had it first, he encourages and recommends it to basically everyone that asks about it. Always saying "it gets me to be active and wanna do something cuz I gotta hit my daily goal." He says he wants to lose another 15-20 pounds and just hasn't been able to shake it off. So I suggest him join me at the gym. Which brings me to this important point..
If you want a measure of how active you are, I think it may be worth your while. But if you're trying to get motivated and get in tip top shape, it may not last - as in the case of my second friend that bought it out of excitement and hype. So really, think about what you want to achieve. A fuel band (kinda like motivation) will get you started but it's persistence and dedication that will get you results.