The most important new capability to note here is the “Export Complexity” option. This option will control how much detail is exported to the gbXML model from your Revit model – ranging from only the basics, to how “shading surfaces” are handled, to whether curtain wall mullions are counted as shading surfaces. The Revit 2010 gbXML export dialog gives you the ability to examine an analytical model of the project before exporting to a gbXML file. You can isolate rooms and view individual surfaces, surfaces are color coded based on type of analytical surface,rooms are grouped based on level and you have the ability to define energy data previously only available through Project Information dialog box.

exportgbxml

Via IMAGINIT blog and CAD Application Development