A suggestion only.
Aid single keyword search and retrieval to aid search, retrieval, information sharing (like Flickr, Delicious etc).
Q's from review:
What is the explicit use-case for this requirement?
Does full text search supersede this requirement?
Doesn't the existing Metatdata Key/Value pair feature essentially implement this now (even if it's a bit clunky)?
Would we need a pre-seeding template to allow a pre-determined set of tags and should this be user-extendable, fixed, or both?
No specific use case.
Deferring until at least 2.3