Another solution to this would be just to use this to set the next event (same time as "nextrun")
PHP Code:
$aotw_next_time = time() + 604800;
(604800 being a week in unix time). Although to be more exact and make sure that both values will be exactly the same ti would be better to use "nextrun" value, I'm not sure if time() will be the same every time (server might stall or something for a second). Any ideas?
You're right that the time that the task runs won't be exact, especially if your forum isn't busy, since it only runs when users request a page (that is, if you're talking about vb "scheduled tasks" and not actual cron jobs). Anyway, maybe another idea would be to let the task run on some regular schedule but have your code check a db field to see if it should do anything.