Updated links: https://www.autodesk.com/developer-network/platform-technologies/fbx-converter-archives

Windows

Mac

Autodesk have provided a bunch of handy FBX converters and plugins at this link.

The goal of FBX is to “constantly and significantly improve interoperability between Autodesk products and other Digital content creation (DCC) software packages.” http://en.wikipedia.org/wiki/FBX

Transfer files from one file format to another quickly and easily with the FBX Converter. This utility enables you to convert OBJ, DXF™, DAE, and 3DS files to or from multiple versions of the FBX format. New tools are now available with the FBX Converter 2012.1. You can view FBX animation files in real time with the FBX Viewer, explore and compare FBX file contents with the FBX Explorer, and manage animation takes with the FBX Take Manager.

Mac *

FBX 2012.2 Converter for Mac (tgz – 33931Kb)

via
Autodesk – Autodesk FBX – FBX Plug-Ins, Converter, and QuickTime Viewer Downloads

Here is a quick video of me converting a OBJ to FBX using the above tool.  In the video I also use the FBXIMPORT command to bring the FBX into AutoCAD.  From there, you could save as DWG and bring into Revit:

PS – This still doesn’t quite solve the Mesh to Solid conversion problem … I am currently experimenting with MESHSMOOTH and CONVTOSOLID.

EDIT:
Here is a vid showing Revit to 3dsMax via FBX.

EDIT Keep in mind that if you import an SKP directly into Revit, it will create materials for each shading material as “Render Material xx-yy-zz” in the Material Library.  You can check which is which by looking at the colour on the Graphics tab, but you will need to manually map Render Appearances from here.

Also, remember that you can save all related material resources if you go via 3dsMax.
There have been many posts about how you can control Sketchup materials in Revit using Object Styles.  However, this relies on the existence of different layers for each distinct material in the original file.  If you have an SKP file and would like to create the layers you need (without using Sketchup itself), you can use this method:

  1. Import Sketchup SKP file in to 3ds Max Design
  2. Export as FBX file
  3. Use Import command in AutoCAD, choose the FBX file – choose to have a layer for each material (Assign Objects to Layers – By Material)
  4. For some reason, I had to untick the Block option – otherwise the file would not import at all.
  5. Save the DWG file
  6. Import to Revit – you now have granular control over each Material / Layer combination through Object Styles…

Note – this method uses only Autodesk tools, it does not require Sketchup to be installed.  If I remember correctly, you can instruct Sketchup to export different layers for each material when exporting a DWG (?)

If you have an alternative way of doing this, feel free to comment.