Above is a 3D Camera view of an ArchiCAD IFC file opened in REVIT Architecture 2010. You do this by using the 'Open' button on the new Application Pull Down Menu. This is not an Import it is 'Opened'. Then you can save it as an RVT file. I got two warnings when I opened the file. One for detaching certain elements and one where I had to click 'delete' on some 'cut out' objects. Then there was some massing objects I could not figure out so I deleted them. All the wall, door, roof, window, furniture objects etc get converted to Families and organized by category in the Project Browser which are usable.
The walls stretch with grips etc. but I could not get them to 'attach' to the roof.
The hosted objects like doors and windows are usable as they are but not really modify-able even if you 'open the family' for editing. Materials do not seem to come through either hence the 'default' material everything is inheriting.
The floor plans look good.
The Levels come in ok and the views all get setup in the Project Browser.
I don't see any annotations or dimension so I will have to check with my ArchiCAD source.
I also opened this IFC in REVIT Structure which looked the same after I did some discipline related changes. So in summary, I am somewhat impressed and depending on what you needed the file for, it is usable as is. I would still re-create my new objects with native REVIT objects. Be it Architectural or Structural objects.