StarCraft II v2.1 Patch Released, Trailer Available

Available via in-game autoupdater
Blizzard Entertainment has issued a new patch for StarCraft II: Heart of the Swarm adding Extension Mods, which consist of parameter sets that can be published to Battle.net for use with any StarCraft II melee map - players can apply any Extension Mod to any melee map from the Custom Games list.
In addition, the entirety of the Arcade, along with all of the maps, mods, and games found within, has been made accessible to all StarCraft II: Starter Edition players for free. All Custom Games are now available to Starter Edition players, who also have access to all three races now.
Moreover, the level cap for each race has been increased from 30 to 35, and the original StarCraft and StarCraft: Brood War soundtracks have been re-mastered and made available for play in StarCraft II.
A video presenting all the changes brought by this update is locally mirrored.