[Please reference this post if you have not previously read about VFP-TMM.]
While it probably seems like a boring topic, the revisions to frxCursor are absolutely critical to all the extensibility stuff we added to the Sedna-SP2 Xbase reporting components, so I chose it for my second TMM entry.
The way it exposes memberdata both makes it easy for multiple authors and extenders to share a common metadata framework and also articulates our recommendations for how expressive metadata can be written for many different needs. That's kind of a mouthful. When I get into the conceptual topics I hope I can say a lot more about this, but for now you need the critical frxCursor public methods doc'd, and I've tried to add some helpful remarks into this topic as well.