This is kind of funny, because it's what I've been using an Omron to do for years now. I know that I have a tendency to be extremely uneven from day to day, and that can be a problem if I am not aware of it (why am I so tired today? *looks at pedometer* Oh, yeah, that'd be why my feet hurt.). I don't have any of the spreadsheet-y tracking that FitBit has -- I just have in my head that I want to be above a certain level and below a certain level (and those levels change if I'm sick, for example).
Nice to see other people are finally using these tools to do something other than the Mindless More Is Better.