I na press release NCSoft announces the introduction of their microtransactions system for in-game items, NCCoin. The first game to get this is the mech game Exteel, but the press release indicates that other future games as well as existing games may also get into NCCoin at a later stage.
Which other existing games will get NCCoin? With this model being more accepted in Asia my guess is that the Lineage games might get it. Neither Tabula Rasa nor City of Heroes/Villains are particularly item centric games, so they do not seem very likely targets. Getting enough in-game currency to buy stuff one may need is not a big problem in either game either, although City of Heroes/Villains have started to get plagued by rare item farming activities, so perhaps there are some opportunities to squeeze some cach out from farming players there.
I’m not sure about the viability in Guild Wards for this; it was too long ago since I played it and I never got very far in that game anyway.