JIMCHI's response made me check out the web site again. The last time I ordered an award online (April, 2002), reservations were not required. Now the on-line instructions state to make the reservation first but the on-line award order form does not look like it requires a resevration number.

My guess is that Marriott was experiencing a lot of people ordering award certifictaes and then finding out their desired property has either no award rooms available for their dates or the dates are in a blackout period.