Patch 2.0.4 brings a revamped interface to StarCraft 2, along with community features such as clans, groups and a "players near you" search. All the upgrades in the patch will be present in the game's first expansion, Heart of the Swarm, when it launches March 12. Last month, Blizzard released a video overview of the new features.
Installing the v2.0.4 patch will be a two-step process. To start, a box will pop up asking players to reconfigure their game installation, which will take about 15 to 60 minutes. After the optimization, the patch itself will begin downloading and installing; partway through that process, once enough data has been downloaded, you'll be able to start playing. Blizzard noted that players who haven't allowed the full patch to be installed may run into "some gameplay hiccups."
StarCraft 2 players can enable a background download of the v2.0.4 patch right now. The patch will be available "in a few days," according to Blizzard.