REVIT to ArcGIS
Although, far from being an integrated system, I still have a need to get data from REVIT into ArcGIS. Here is the path I used last time I did this to create features in ArcGIS. You may find other paths to get there. Working with one DXF file exported from REVIT. The resultant AutoCAD file contained 3D entities that ArcGIS doesn’t support (Polymeshes). However, exploding them with the AutoCAD EXPLODE command did create 3D Faces that are supported by ArcGIS. From REVIT I can also export data to a 3D Studio file (.3DS). I could have used ArcGIS at this point to bring the entire 3DS file in as single 3D symbol in ArcScene or ArcGlobe, but I wanted to get the individual building parts as separate multipatch features. I imported the .3DS file into plain AutoCAD, which generates 3D face entities directly, the type of 3D CAD entities ArcGIS does support as multipatch features. The resultant AutoCAD file could then be used in ArcGIS.
To make the drawings even more usable I created separate muiltipatch feature classes using ArcGIS for AutoCAD for each different building part that were easily destinquished based on their AutoCAD Layer. Now when I add the data from either of the two AutoCAD files in ArcGIS I get 3D multipatch feature layers that correspond to the different building parts. I can also use the existing CAD georeferencing tools of ArcMap to position my building in geographic space, and migrate the data into a geodatabase if needed.