Sweatshop or no sweatshop, I've always found the practice of selling in-game items or currency for real money to be pretty gross. Obviously, this issue hits massively multiplayer games harder than most, as only crazy people will bid on, say, a high-ranked Call of Duty 4 account. Some people like to justify it by saying they only really have fun with the endgame of an MMO. As far as I'm concerned, if you don't have fun building up a character, you probably shouldn't be playing an MMO to begin with.
Warhammer Online's stance on gold selling has been made crystal-clear thanks to a blog post from Mythic's CEO, Mark Jacobs. His approach involves what he calls a "strike team" that is charged with straight-up banning people who are advertising gold for sale via the game's chat channels. In less than a week, around 400 accounts have already been banned.
This sounds like a pretty good start, but Jacobs is quick to point out that it will be a "long and costly battle" and that this is only their first step. It'll be interesting to watch and see how they try to stay ahead of the problem.