Well I just started using Blender again, but I have noticed one thing that holds me back from using blender to a greater extent is not being able to save my files in another format, such as .3ds, NDO, WRL, MDL, OBJ, ect. if we could expoprt to these formats we would be able to take advantage of the great modeling abilities of Blender, texturing, and then being able to take advantage of other great features in other programs. I would love to see this added in next addition to blender, and it would make more willing to model in blender knowing that my models are not restricted to just Blender.
Most of these are in fact already supported, though you need to use pythonscripts to make it happen.
However, native (non-scripted) support for reading and writing OBJ and 3DS would help a lot. These are probably the most widely used and supported formats and should be enough.
For instance: having a full-blown 3DS support would make it incredibly easy to use VirtuaLight for rendering.... And so on and so forth...
_________________eXo.Entity - the movie-in-progress-project