Revit 2013 Update Release 1 is now available and this time there is no need to do a full install instead service pack technology is being used. Download links below as well as a list of all enhancements.
  Downloads:
  Revit Architecture 2013 Update Release 1: DL20121970 (Applies to: AutoCAD Revit Architecture Suite 2013 and Autodesk Revit Architecture 2013)
  Revit Structure 2013 Update Release 1: DL20122015 (Applies to: AutoCAD Revit Structure Suite 2013, Autodesk Infrastructure Design Suite Ultimate 2013, Autodesk Plant Design Suite Ultimate 2013 and Autodesk Revit Structure 2013)
  Revit MEP 2013 Update Release 1: DL20122070 (Applies to: AutoCAD Revit MEP Suite 2013 and Autodesk Revit MEP 2013)
  Revit 2013 Update Release 1: DL20121968 (Applies to Autodesk Building Design Suite Premium 2013, Autodesk Building Design Suite Ultimate 2013 and Autodesk Revit 2013)
  Improvements made in Update 1 build (20120716_1115):
  Autodesk Revit Platform 2013 Enhancements     
- Improves stability when opening projects from previous versions of Revit.     
- Improves stability during Copy/Paste operations.     
- Corrects display of solid filled regions with transparent backgrounds.     
- Allows exporting of materials painted on elements to ODBC.     
- Improves performance of opening and closing sketch mode in projects with many families.     
- Improves stability when setting a Design Option as the Primary.     
- Improves stability when Fixed Distance option for a divided path.     
- Improves stability while browsing to Revit Server when there is no network connectivity.     
- Improves export consistency of Space and Zone elements when multiple elements have the same name and number.     
- Allows Raytrace mode to work with DirectX 9.     
- Improves stability when using Raytrace mode with Hardware Acceleration disabled.     
- Improves Raytrace mode rendering output.     
- Improves Surface Transparency override by element for multiple selection.     
- Improves printing consistency when tone mapping is enabled.     
- Disables Sun and SunPath from being rendered in Raytrace mode.     
- Improves stability when using manual exposure in Raytrace mode.     
- Improves stability when rendering views.     
- Improves stability and performance when using visualization features like Sky, Exposure, and Anti-Aliasing.     
- Improves stability when importing IFC data which contains special characters.     
- Improves the setting of custom parameter values during import of IFC data.     
- Improves stability when importing IFC data which contains an invalid line pattern.     
- Allows Markups from DWF to be exported to DWF.     
- Improves stability when drag and drop a DWG file into a Revit project.     
- Improves stability when importing DXF data.     
- Improves dimension fidelity when exporting to DWG with export units set to Meter.     
- Improves alignment of hatch and fill patterns when exporting to DWG.     
- Improves stability when selecting a new host for an element within an In-place Wall.     
- Improves section creation within a project with linked model.     
- Improves stability when working with Materials.     
- Improves the displayed Pattern Type assigned to an element with the Material Editor.     
- Corrects the display of the materials category within the Paint interface.     
- Corrects the printed display of fill patterns within perspective views.     
- Improves stability of Type editing when multiple element types are in the selection set.
  Autodesk Revit Architecture 2013 Enhancements  
- Improves stability when closing a sketch editor, such as slab, site, etc., which create a large number of points.  
- Improves creation of U-shaped winder stairs.  
- Improves stability when editing winder stairs.     
- Improves performance when many railings exist within a project.     
- Improves stability when support type is not defined for stair.  
- Improves railing representation in coarse view. 
  Autodesk Revit Structure 2013 Enhancements  
- Improves placement of analytical nodes when in 3D views.  
- Improves stability when enabling “Show Analytical Model Categories in this View” when the Warning dialog is open.     
- Improves creation consistency with Physical Wall when coping an Analytical Model Wall.     
- Improves stability when editing an Opening within an object which spans to the boundary of an Analytical Surface.     
- Corrects the reporting of the “Structural Parameter” on slabs.     
- Improves masking of linked files by Mask and Filled regions in Structural Views.     
- Improves stability when placing Rebar.     
- Improves stability when copying Area or Path reinforcement between projects which have differing value for the Reinforcement Project Setting: “Host structural rebar”.  
- Improves visibility of round rebar when displayed in fine detail level.     
Autodesk® Revit® MEP 2013 Enhancements     
- Corrects the Slope value on placeholder pipe when slope is greater than 15 degrees.  
- Improves consistency when applying a slope to a layout which contains a transition.  
- Improves stability when splitting pipes which belong to different systems.  
- Corrects visibility of the center line when displaying rise/drop symbols.     
- Improves stability when opening a Revit 2012 project which contains a pipe placeholder schedule.  
- Improves consistency of unit formatting within Panel Schedules .     
- Improves consistency of adding circuits to equipment that are connected to a pipe or duct system.     
- Improves stability when adding a device, which is connected to a wire, to a circuit.     
- Improves display of annotation on duct and pipe transitions.  
- Improves stability when inserting duct fittings.  
- Improves stability when viewing Routing Solutions.
  There are also several Autodesk Revit API 2013 Enhancements:     
- Allows Document.PostFailure to be used to post multiple errors during a single transaction that do not reference an ElementId.     
- Improves stability using UIApplication.DoDragDrop when a Revit command (such as the Wall tool) was active.     
- Improves stability by disabling keyboard shortcuts (except view zoom shortcuts) when a PreviewControl is active.     
- Improves stability in ReferenceIntersector.FindNearest() when no matching target pick is found.     
- Corrects validation logic to allow NewFamilyInstance to place face-based families on transformed family instances.     
- Dimension.Above and Dimension.Below now update the dimension after their data is changed without requiring any user action.     
- The properties MechanicalSystem.SystemType, ElectricalConnector.SystemType,     
PipeConnector.SystemType are obsolete in Revit 2013. Instead query the parameter     
RBS_DUCT_CONNECTOR_SYSTEM_CLASSIFICATION_PARAM on ConnectorElement.     
- Corrects data reported with ConnectorManager.UnusedConnectors.     
- Fixes a file corruption that could occur when extensible storage data was added to an element in a central file.     
- Improves stability when saving a file with extensible storage data that overwrites an existing file that also contains extensible storage.     
- RVT Links created with RevitLinkType.Create will remain loaded when the RVT containing the link is reopened.     
- Previously, setting 'suppressBendRadius' to true in method Rebar.GetCenterlineCurves() would cause both fillet bends and user-drawn, parameterized arcs to be omitted from the collection of curves returned by the method.  The method now omits only the fillet bends; the drawn arcs are included along with the straight edges.     
- Updates Rebar.GetCenterlineCurves() method with an additional argument: a MultiplanarOption (enum), which should be set to IncludeAllMultiplanarCurves or IncludeOnlyPlanarCurves.  This argument controls whether all curves of a multi-planar Rebar instance are returned, or only those which lie in the primary plane.     
- Enables method Rebar.ComputeDrivingCurves().  This method returns a collection of curves that includes the lines and arcs that drive the shape, but excludes fillets and hooks.  It is equivalent to calling GetCenterlinCurves(adjustForSelfIntersection=false, suppressHooks=true,  suppressBendRadius=true, multiplanarOption=IncludeOnlyPlanarCurves)     
- Improvements have been made in RebarShape methods that deal with matching RebarShapes to collections of curves: CreateFromCurvesAndShape(), RebarShapeMatchesCurvesAndHooks().     
- Corrects behavior ot RebarShape.Create() method to not ignore the out-of-plane bend diameter specified in the RebarShapeMultiplanarDefinition argument object, and always used an internal     
default value.