Once it hits "0" (assuming it's not a case of bad data and you're really at the top of the list), you are next in line to be offered a slot.
When you are offered a lot, a link allowing you to pay for your slot will appear on your USPSA classification record.
You should see the # ahead decrease as time goes on, but this won't really start happening in any serious way until after 4/2 which is the duedate for the outstanding slots (those not returned are voided).
Thanks Rob. I am still holding at #2 (if this is correct) for the Limited Nats. I would hope some or most slots get handed out before July as I (and I'm sure most others) have to plan vacation time, make reservations for the hotel and car rentals, etc. etc. etc.
Tom (Mainus), what is your place on the wait list?
Dave