... Uh... are you really comparing Torchlight to d2 to prove a point about multiplayer models? They didn't even try to have multiplayer, and the itemization is completely and utterly different. Wait until Torchlight 2 to see how that particular fiasco ends up as. I predict terrible, but not because of the multiplayer model, but because the game is a Mythos clone with horrible design behind it. If anything, mod support could catapult it ahead of D3 in terms of depth and flexibility.
Mythos is a free to play MMO and has been from the start. Just like Requiem, Dragon Nest, ect. and the reason it has a cash shop is because it's a free to play MMO. I think the reason that Blizzard chooses to have an auction house to slap huge fees onto is because they know they will never be able to conquer botters and hackers, so they're aiming to instead plunge their dick into the inevitable circus that the economy is going to yet again get puckered into, but in a manner that allows them to distance themselves from needing to maintain something like a cash shop.
The auction house is the perfect way to attract monetary value in this way because even though there will always be third party transactions going on, this setup allures dimwits into thinking they're going to become e-millionaires by playing the game. A cash shop needs to maintain ingame economy value and reasonability which means paying attention - Blizzard knows damn well their overfed interns couldn't play their own games for shit much less keep up with the economy, so they instead apply a business model that allows hands-free operation.
D2JSP is a huge trading forum that those who remain dedicated to d2 are at least somewhat effected by. If Blizzard introduced a cash shop this will not prevent similar things from cropping up in the future, simply because they act as a hub for commerce. Although a standard auction house alone would probably be sufficient to prevent such competition, why not introduce incentive to get players to dump money into the game and avoid all of the ickyness associated with independent cash shops? In fact, this move is on the verge of the same brilliance as introducing paid mounts in WoW. They are going to make a killing if D3 can stay afloat.
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