PVP Medals are paid out once per week on Monday nights (Midnight PST). This is an automated process, and your expected payout total can be viewed from the Gear Store. This modal also includes a timer which counts down to payout delivery.
NOTE: If your total number of medals does not update after the scheduled payout time, remember to clear your Flash cache and refresh your browser before assuming you didn't get your medals. Your computer may just need to re-sync with our servers to load the new information. It is actually very rare for the medal payout to fail, so try this before ticketing in to ask about your missing medals!