You can go check on the payout queue page. (http://eligius.st/~wizkid057/newstats/payoutqueue.php) A good rule of thumb is that you will never receive two payout faster than the "age" of the last payment in the first block of the queue. AND THAT, REGARDLESS OF YOUR THRESHOLD.

If your theshold is set such that you cross it at longer intervals than the queue time, you will be immediately payed when you cross it. If you cross your treshold at a shorter interval that the queue time, your threshold essentially does nothing (it might as well be 0), and your payout interval will be entirely dependent of the fluctuations of the queue.

The last payment of the first block, at the time of writing this, is 1 week, 6 hours and 29 minutes old. People who have received their last payment earlier than 1 week, 6 hours and 29 minutes ago will have to wait longer before their payout.

A queue longer that a week is a bit long I admit, usually it is more around 3-4 days, but it is not unheard of. However, wizkid has stated earlier in this thread that he will do a manual payout soon, which should help shrink the queue.