Well, it's definitely true. Blizzard has killed LAN support in the upcoming StarCraft II, and here's the official word from Bob Colayco at Blizzard PR:
"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. 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.
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. We're looking forward to sharing more details about Battle.net and online functionality for StarCraft II in the near future."
So, let it hereby be noted that pirates killed the LAN parrrrrty.