Flavia and Mel have recently had good posts about the MLA Job Information List, with Flavia talking about wondering what might be out there and Mel about the anxieties it raises even if you're tenured and happy.
I used to look at the JIL (and the Chronicle), and, such is the power of the feeling as though you're "cheating" on your current job, even after I had a job I liked and was tenured, I'd make sure the office was deserted before I checked out the paper version.
For the past couple of years, though, I haven't looked at it at all, unless our department had an ad in there or was in the process of writing one for a search. It's not like giving up Bloglines or something, either, where you have to stop yourself from looking; I just stopped and didn't look back. I don't miss it.
Does this mean that I no longer have goals I want to reach or things I want to accomplish? Of course not; it's just that the things I want to do (promotion, eventually; lots of research projects) don't have anything to do with what had become, for me, the huge time suck of dream job/anxiety that the JIL inspired.
Looking at the list can serve a lot of good purposes, and people want to move for all kinds of good reasons, but I'm talking about feeling compelled to consider this option every fall the way a lot of us do. What kind of profession is it that makes us think we aren't "successful" unless we're always anxiously searching for something better than what we have? Academics, that's what.