"We don't currently plan to support LAN play with Starcraft II, as we are building Battle.net to be the ideal destination for multiplayer gaming with Starcraft II and future Blizzard Entertainment games," a Blizzard representative said in a statement. "While this was a difficult decision for us, we felt that moving away from LAN play and directing players to our upgraded Battle.net service was the best option to ensure a quality multiplayer experience with Starcraft II and safeguard against piracy."
That statement sounds a bit self-serving to me, as most people don't care about piracy problems (even if they are real.) The justification for the decision should really be in support of Battle.net, a case where "cloud" supposedly means more than just an Internet connection, offering a platform that enhances the game play and leads to more interaction amongst players.
"Several Battle.net features like advanced communication options, achievements, stat-tracking, and more, require players to be connected to the service, so we're encouraging everyone to use Battle.net as much as possible to get the most out of Starcraft II," the statement continued.
Some users lament the idea of cloud game platforms as causes of latency and other possible game-play issues, but I suspect that things will balance out. Most online games are already pretty good at making the most of available bandwidth and odds are the new features will encourage users to stay on regardless.
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