From the Lab's description:
- With eTransmit for Revit, you can:
- Copy and detach a Revit model and associated files to a single folder for internet transmission. This removes the typical error messages when you copy central files using the operating system.
- Locate dependent files automatically and include them in the transmittal folder, reducing the possibility of error. All dependent files are automatically converted to use relative paths to ensure that the dependent files can be located by the model.
- Choose to include related dependent files such as linked Revit models, CAD files, DWF markups, decal images, and external keynote files. You can transmit any Revit (.rvt) model that has been upgraded to Revit Release 2012.
- Transmit models that are using file-based worksharing or server-based worksharing. eTransmit for Revit will also work with non-workshared Revit models.
They've got a Known Issues PDF you can check out too.