I cannot install the Three.js plugin for Blender. I have a Fedora with Blender 2.69, I created the directory io_mesh_threejs in /usr/share/Blender ... /addon and copied the 3 .py files into but the plugin doesn't appear in the user preference.
I also tried with a downloaded 2.65 version of Blender with no success.
I did it for another library (Babylon.js) and it worked fine so I guess it comes from the python files ?
Here is what I did to get it to work with Win 7 - may work for you also.
Make sure you copy the text from the Raw File format instead of just right clicking and downloading the python files. If you right click and download you might get some additional html code that will break it. Someone else here made that suggestion previously.
Put the import and export files in the io_mesh_threejs folder. Put the init file in the root of the addons directory.
That did the trick for me anyway.
hopefully this adds to the conversation stream ... I've spent two hours finding this answer myself for IFC file imports for Blender ... I've just now got there ... I'm on a Mac with OSX and my Blender 2.71 is positioned in /Users/username/Documents/Blender ... I tried the User Preferences to no avail ... even followed the PATH to /Users/username/Library/Application Support/Blender/2.71/scripts/addons and manually copied the files in using shell ... still nothing ... then I found that the actual place they should go is
/Users/username/Documents/Blender/blender.app/contents/MacOS/2.71/scripts/addons
In my case for IFCBlender I then made a directory called
bash$ mkdir io_scene_ifc
Then I copied in the all the downloaded files ... Hooray this now appeared in my User Preferences ...
