@Arrohon

Yes, this occurs, but far less frequently than it would with an in-game auction house that facilitates these transactions. As it is now, somebody in another guild could be buying gold to get new epics that much sooner than me. They're not supposed to do this and take a number of risks in the process, ranging from account theft by the third-party seller to account suspension/banning by Blizzard. Gold sellers and buyers already affect me indirectly in this way, but Blizzard can only do so much policing on this front. I'm satisfied that they're doing what they can and hopeful that in the future they'll have better tools for combating this behavior.

My other examples, however, aren't currently in-game concerns of mine. Guild leaders cooking the books? Ninjas being given yet another reason to take crap they don't need, since we've now given it monetary value? Progression raiders being given a strong incentive to buy items to keep up with the competition? Not to mention that this all inflates the gold price of items, since there are now two sets of currency. Granted, this works both ways, as items both cost more and sell for more, but it still puts a "financial" burden on somebody leveling a character on a new realm. For me personally, it also devalues my in-game work and achievements. If it costs $3 to buy an epic that took me days of farming and dailies to afford or craft, I'd feel a little slighted. Of course I could just buy it myself for the same $3, but my incentives for the game end up out of whack. I don't want to have to buy my way to success or fall behind as a holdout against the new system.