For all of you out there that are waiting for a word about Civil 3D 2013 Service Pack 1 (Update 1). Here it goes. In a continuing effort to provide high quality products, Autodesk has released AutoCAD Civil 3D 2013 Service Pack 1, which fixes or addresses a variety of issues discovered by customers and by Autodesk's internal testing team.
As always, please take a look at readme to get familiar with fixes and installation instructions. You can get it from here.