Let me ask you this question, would you rather pay $20 for one episode (How many episodes are there going to be ?) or a full game for $49.99-59.99 ?
Well, that depends on the amount of content in the episode, doesn't it? If it's half of a full game then clearly the episode. If it's less then, well, probably the full game, if only because I won't buy it until it's much cheaper.
The amount of episodes is irrelevant and I can't understand why this keeps coming up. If the demand is there Valve will meet it. Milking? Not if people want it. Only if they saturate the market. And there's clearly demand for more HL.
The problem with episodes is in the amount v. price, and the time between. If everything was perfect we'd get 8-10 hours for $20 every year or just under. How could you complain about that?
The problem is in getting 4-6 hours of the same price in almost any time. You're paying a bit too much and, right when you get into the game, it ends and you're left unsatisfied. Episodic content only works in certain ways. This is why it's so rare in most media - people don't like waiting, especially if it's right when they begin to get into something.
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