I refuse to buy games whereby they milk you with umpteen expansions, each of which cost 60% of the orignals price and only add less than 10% of the content or where the content is sold it expensive packages where you pay over 20p for a single piece of graphics which took the develop under one day to compose.
Spore already has done this with its creature editor, its main game, its mission expansion, its piece expansions and I am sure there is one more expansion out.