I'm actually trying Revit Architecture 2012 in combinaison with 3ds max 2012 in order to test the transfert between them. Most of the process works properly but is not more than satisfying. There is some improvements that could help to bring the transfert more interesting.
1. Actually "unit scale" is simply not supported; if I set a revit model in imperial inches and then try to import the model through FBX in 3dsmax (where system unit is set to inches) I see "feet" for "System units" in the statistics panel of the import windows before. The result is finally in inches, I can confirm it by simply placing a box at a specific size next to an imported object that I know its real scale. So why do I see "feet" in the import panel? Also, I try to import the model by using the "Autodesk Media & Entertainment" preset instead of the "Autodesk Architectural (Revit)" and choosing another unit (Advanced Options > Units > File Unit Convert To) then I get always the same resulting geometry. So it seems that no scale can be applied while importing which is a big turn down when working with a project that uses many different units (almost every project in my case).
2. Material are not scaled correctly. By using the same settings (revit model in inches than tranfert in 3dsmax), I get the model in inches as I said previously, but all uv mapping scale on geometries are in feet! This is a bug; I need to scale down each real-world bitmap I apply to the model by (1 / 12). So this needs to be corrected really soon!!!
3. The standard "Autodesk Architectural (Revit)" preset in 3dsmax needs at least a unit scaling feature that works (as I said previously) and also the possibility to filter imported objects like lights and camera. The transfert process is never a one-time task for a project, we need to do it almost at each modification to update the visual... so the process need to be the more "simplified" as possible. I can edit my own preset, but I think Autodesk should add these on their side.
4. Revit Architecture should have at least have a "save selected objects" feature and allow to save to FBX without having to select a view previously. Actually, during a modification process I have to select the modified objects, isolate them, set the view to 3d, and then export the view to FBX. A very long process, for a simple task.
5. The geometry transfert needs to be more flexible. Actually any familly are transfered as one single object mesh which is not always suitable for a door familly for example. Just by wanting to open a (door created in Revit with a frame) within 3dsmax is enough to explain my point. So I would like to see some new properties in Revit Familly Object to control the way Revit export each objects. So when I need to do a transfert, I could get a door within 3dsmax that could be an assembly of 2 separated geometries (frame and swing) that I could animate properly within 3ds max. Also, as FBX meshes the geometries, we need to control this approximation for each object within Revit (as a new property), especially for the curves. Actually, if I create a ceiling with some recessed light fixture (round), then transfert them to 3ds Max, I get some major differences between the hole created in the ceiling and the fixture.
6. My last point is for a future connection improvement for all Autodesk products. I would like to see a kind of virtual connector between applications. For example, if I have Revit Architecture and 3ds Max open at the same time, it would be really interesting to have a new button next to the import in 3ds max which list the actual opened Autodesk softwares... then we could select one in the list, then select the file, and then specify is we transfert all the file or the selection for example, and then this connector could do all the communication between both software to save the objects in Revit then push the result to 3dsmax and import, in one single action... I think all this could be done as a kind of clipboard transfert, so need to create temporary file, and this should be quicker. Autodesk FBX is probably a of the answer, but FBX need to be more connected, some kind of "FBX live".