Icons look good, however having each file type associated with another icon involves changes in code and while this would be nice, we still have more urgent priorities.
Here is what I can do. If you want to help you are welcome to create sample icons in ICO format that contain 16x16 (yes, 16x16 is a tough one, but it is a must) AND 32x32 AND 48x48 sizes both in XP and 256 color mode (this is mandatory to fit UI standards). There should be an icon not only for the 4 most popular but for all supported file types or alternatively there can be perticular icons for most popular types and some other icon for all other less popular types.
Another issue is that as we have a product line of not only WeBuilder but also other code editors, it might be more feasible not to integrate W icon in the document type icons, this way it would be possible to avoid creating separate icon sets for each code editor we distribute.
As you can see, the complexity of the task is significant

This is why we have had no time to do it so far.