Cosign. I have one of the Withings scales and weigh in multiple times a day. I don't fret over fluctuations -- and I might fluctuate 5lbs in a day -- it's the long term trend line that matters and I can see it on the Withings site. Adding more data just helps.
Have you considered tracking skinfold measurements too? I know my weight can fluctuate a lot just from inflammation response after a hard training run. Weight seems to have too many factors that vary at different rates for different reasons.
