The final part of the StarCraft II trilogy, Legacy of the Void, is set to drop next month on PC. But before then, all fans, regardless of whether or not they've purchased the new expansion, will be seeing a UI overhaul. The revamp is being touted as a more social experience, with support for multiple windows, better chat, a cleaner UI in general, keyboard shortcuts, and a better arcade.
One great feature I've seen pitched from the community is the option to select the title music, going all the way back to the original StarCraft. Make it so, Blizzard.
New User Interface Coming to StarCraft II [Battle.net]