I think mine arrived in about 3 or 4 weeks afterwards. I know I was concerned because I wanted to get it before I went to DL cause I wanted to use the discounts. (My initial purchase was thru resale so I didnt get a temp card).
BTW, rogerram, I think EpcotKilterFan was referring to the temp card expiring. The regular member card don't expire until you do... or until you sell your membership.