I agree that it's probably different for everyone, depending on how crazy it makes you feel. I do weigh every day and then enter it in a spreadsheet that turns it into a graph for me. Then, over time, I can see patterns developing. I've only been doing it this time for a couple of months, but when I did this a few years back I had a definite pattern of steady loss for two weeks, then an upward spike. Then I'd apparently get myself back on track for another week until my TOM, with the inevitable fluctuation. Then I'd go back to my two weeks of steady loss, another spike upward, etc etc. Wierd, huh? But very useful information. I haven't lost enough yet this time to notice any patterns, but it'll come.
-Lala

And I agree with you, when I lived with a scale I would be on it all the time, freaking out if I gained a pound, and then I realized that who really cares what the scale says so long as I look and feel good? So that's what I'm really working for... but I still have my little (probably outdated) tracker anyway. 