So not only Starcraft 2 will not have LAN access, but also Diablo 3 will be without this option.
http://www.pcgameshardware.com/aid,689265/Diablo-3-like-Starcraft-2-without-LAN-support/News/
http://www.pcgameshardware.com/aid,689265/Diablo-3-like-Starcraft-2-without-LAN-support/News/