As noted by Steve Stafford & others, update release 3 has been released for Revit 2013. For the specific building design suite version, this can be downloaded from here:-
General platform improvements for this build include:-Improves stability when using Hardware Acceleration, Graphics Mode.
Improves stability when opening projects which utilize Extensible Storage.
Improves visual fidelity between canvas and printed output.
Improves visual fidelity of hidden lines, MEP pipe centerlines and haloed gaps when not using Hardware Acceleration, Graphics Mode.
Improves Structural family data integrity during upgrade of project.
Improves data integrity when canceling Save As operation.
Improves interaction between Revit Server 2013 and Riverbed compression.
Enables users to browse Revit Server Networks when a bound workstation cannot contact the Domain Controller.