How do we get a count of the different file types indexed by SharePoint 2010's Enterprise Search? For example, we'd like to have a count of all the *.docx, *.xlsx, etc.
I can't think of an efficient way of doing this apart from tagging all documents.
The simplest and probably most efficient solution I can think of is, to do this on an event receiver when a document is added to the library, then writing an update script to set all the values of anything updated previously.
You could do this in a good afternoon and have it tested for the following lunch time for deployment.
Then it would be easy to collate the taxonomy counts. Either use the refinements panel or lookup this Managed Metadata Web Part on CodePlex.