I've been working mainly in Wings3D while using Blender for secondary things like flat/double-sided sufaces and rigging/animation. The one problem I've been having working between the two is getting texture coordinate information into Blender. Wings exports 3DS files correctly with UV coordinates, but Blender just can't seem to load them. I may need to write my own 3DS importer just to get some integration going.
I started playing with Erlang to make some native exporters for Wings. It is certainly the most unusual programming language I've encountered so far. I'll probably play with it some more over Christmas since Wings exporters aren't much of a priority.