PREFACE: What you are about to read is not your typical review. There are already plenty of sites dedicated to reviewing the basic function of these devices, giving you a run down of the physical specifications. If that is what you are after, check out Fitbit product-related articles on Engadget or Tech Crunch.
Instead this review is going to dig deeper, show results & data compared to other options run in tandem, and discuss the practical use of such data. I’ll apologize now for the verbosity of this post.