It's at $20, very rare a PC game ever goes below that price threshold, expansion or not, unless it sucks, and WoW does not suck obviously ;p Price won't drop, may as well get the expansion now, especially if you wanna roll Draenei/BEs or lvl in their zones(Which are FAR superior to the pre-bc zones + better loot, no stupid +str +spi bs items on your mage/lock lol)