Luckily many of the answers are not too surprising, it seems in general the tool is being used as I had expected. And the features people are missing are those that I had on my wishlist already. And of course there are always some nice new ideas, so I will put those on my wishlist as well.
I would like to put some more focus on two of the results that surprised me most. First the COLLADA DAE format seems a lot more popular than Google Earth KMZ to import models from Sketchup. I find this a little surprising, since I had expected KMZ was more popular. I think the advantage of KMZ is that the textures are contained in it as well, so you never loose them. But it seems most Sketchup users use COLLADA DAE files instead.
Another thing that surprised me even more is that import SCASM files and API macros is not popular at all. Even the recently added functionality to import COLLADA files is more popular already. Since I started developing this tool to convert my old API macros over to the FSX MDL format, I was a little surprised to see that most people perform other conversions with the tool. I guess you could almost say that the tool has a sort of mid-life crisis and is transforming into other functionalities as well.
Once again, thanks everybody for your feedback, it is really interesting to get an overview of how you use the tool!