In reply to Juego.

Well, I have it working in a script I wrote for importing data to a webGL-based 3D geoportal. In short, I use python (with ArcGIS' arcpy module) to load kmz (collada + kml) building models into PostGreSQL database (I need it there for some testing of spatial relations between the kmz and other spatial data), and then export it back to collada (ArcGIS does a much better job importing collada than blender and it exports collada in a simple constant form, which is much easier to process automatically in blender than colladas produced e.g. in SketchUp) and then I do some stuff with the resulting collada in Blender (import collada, remove unnecessary geometry, bake consolidated textures, generate lower resolution meshes with smaller textures, generate metadata which our geoportal understands and which describe the models). Then I "do some more stuff" with the exported obj files in pure python. It's not flawless but it works. More or less :)
The other software I considered for automatic meshes processing is MeshLab (meshlabserver), but in my opinion it is not as powerful as blender (mostly thanks to built in python in the latter).