The field of 3-dimensional data is growing more and more but ArcGIS can not cope with standard formats like citygml without expensive extensions. This should be a basic feature of such a great GIS program.
If the "other" programs support Collada (.dae), there is not a problem. ArcGIS reads Collada just fine. Spending resources to provide custom support for many different programs does not make sense. Sony initiated Collada, but it is now administered by the Khronos Group so that no single company controls the exchange format.
