In the past, your account will be upgraded whenever your payment deposited into my account balance. This is advised by 2CheckOut, my payment gateway.
Sometime it takes a long time for money to be deposited, with PayPal is about 1 days, and with credit / debit cards is about 3 days.
As a vendor, I wanna be sure that the transaction has been completed perfectly before process account upgrading.
Thinking as a user, I want to upgrade my account as fast as possible. I paid for service, so WHY you make me wait for a long time?
So, from July 08, 2009, your account will be processed right after verified by 2CheckOut team. This takes only 6 - 24 hours to complete :)
EDITED: it often takes only 1 hour to complete :)