Steve at PlayNoEvil has some interesting analysis up on the current state of gold farming in MMORPGs (though he does admit that since hard stats are difficult to come by, "any analysis is more akin to reading tea leaves"); using data provided by mmobux, he looks at the pricing trends to try and divine what might be going on in the wild world of selling gold:
If anti-gold farming initiatives were effective, gold prices should go up as the cost of business increases for gold farmers. (NOTE: This assumes that demand is fairly constant. If game companies could actually convince their players not to buy gold, than prices would drop with a glut of gold on the market and no one to buy it. I've not been able to get volume data from any gold sellers, but my sense is that their customers are not going away.)
The answer seems to be a stalemate, more or less — something we can look forward to for years to come?
The Gold Farming War - Who's winning? [PlayNoEvil]