Gavin, can you confirm the best place to  read  up on the discuss fee  
estimation changes for v0.9?

I think fee estimation at its core is about providing a data point, or  
even call it an API, which can be used however you see fit.

What parameters do I want to see in a 'fee estimation' API?

  - 30 minutes vs 24 hours processing time
  - Confidence Levels (50%/90%)

What properties does the result have?
   - Is it globally consistent?

Talking about fees.. I read this:  
https://gist.github.com/gavinandresen/2961409 and there is so much there I  
really liked.

Any pointers for reading more about the leading theories on transaction  
fees? For example, how well do they correlate with network security? Are  
we getting what we are paying for? :-)