Perhaps too general or whacky, but here goes...

Think about managing structured data in the wiki alongside the rich text blob.  Example - I want to have a wiki of source code to reuse.  By adding some fields to each 'page' - like "language", "environment", "completeness" - I can force some structure to allow easier viewing.  For example, show me all pages written in C#.   Using a wiki brings a level of ease-of-use and manageability missing to existing libraries. 

Okay, maybe that example sucks - others could be simply adding a 'language' field to an entry, e.g., spanish, english, ... 

Any thoughts?  Does it make sense?  Has this been done somewhere? 

Yes, this would be a pain to add on, i.e., having to track additional elements - and what does diff do?   Any thoughts there, i.e., how big an effort?

Thanks - sorry to post something which is perhaps too b'stormy...