In behaviorism I believe this is called extinction. Given your high frequency of response (behavior of checking this forum) and the contingent reinforcement of seeing interesting discussions or whatever, the behavioral contingency has become very ingrained. Since you occasionally log on and don't see anything interesting, or little activity, you are not always reinforced - it is somewhat unpredictable. This is called a variable interval schedule of reinforcement. Typically this results in a high response rate (eg. checking SDN several times an hour).
The Thanksgiving server down time meant that the interval during which you were not reinforced was longer than usual, perhaps explaining your lowered response rate. However, since this behavioral contingency is still present in your learning history, it shouldn't take long for you to be just as hooked as before 🙂 Variable time interval schedules of reinforcement are difficult to extinguish cause you're always wondering if your next response (ie. going to SDN.net) will be reinforced.
Wow, don't know where that came from! I am such a geek 🙂 (Well, I do have a behavioral psych exam in a few days so I guess I can sort of justify...)
cheers,
thatuvicguy