As developers of discovery and access tools, we run into the situation where we discover a resource in a remote catalog and have to understand the specific type of that resource so that our clients can work with it. This is not a geo-specific problem. No one who has opened a link that ended in .pdf has ever been surprised that the resource on the other end of the URL was opened in Adobe Reader. Somehow my system recognized this to be a document and saw I have a client installed that can work with that document. This was not because of the .pdf extension, but thanks to the fact that the PDF came to me with a MIME type (maintained by IANA).
I found an old blog post on the OGC website where someone asked about dropping OGC-specific MIME types in WMS 1.3.0. The question remains unanswered in the blog since May 10, 2005...
I pose that defining MIME types for various geospatial resources (from file storage types like ESRI Shapefile to web services like OGC WMS) will benefit users of these geospatial resources and developers alike. Here I'm not speaking of the data/images obtained from these services, but (in OGC case) recognizing the service endpoint as such.
