Via Terra Nova comes a fascinating paper by Richard Heeks that covers the historical, social, and economic aspects playing into real money transactions. I've just had time to take a quick gander at the paper, but unlike a lot of information out there, this appears quite comprehensive and with a more unbiased position than we usually see:
This paper reviews what we know so far about gold farming, seeking to provide the first systematic analysis of the sub-sector. It assembles available data at the sectoral, enterprise and worker level. Five main analytical lenses are then applied. Economic analysis shows how exchange rate variations and scale economies do and do not impact gold farming; and the strong influence of information failure in the purchase of virtual items: known as "real-money trading". Analysis from the perspective of industrial sociology charts the commoditisation and globalisation of the sub-sector, while value chain models identify resource dependencies and power inequities. Enterprise analysis investigates enterprise entry, existence and progression, and outlines the competitive forces shaping the sub-sector's development; particularly threats. Developmental analysis investigates the impact of this sub-sector in macro and micro terms. Finally, there is a sociological analysis of the role played by perceptions and other social forces.
I've got it saved for future reading, and from what I've seen, it's definitely worth a look if you're interested in issues of RMT and gold farming. It is long (and academic!), but think about wading through if you're feeling inspired.
Current Analysis and Future Research Agenda on "Gold Farming" [IDPM Working papers via Terra Nova]