We agreed on the basics of a format for centroids to enable query routing. The Stanford informal agreement already includes all these headers, with the exception of the Administrative contact. This mailing list will serve as the forum by which members of the Query Routing Working Group can express their ideas, voice concerns, etc. The idea is that the RFC and suggested modifications can be implemented and we can see what problems arise therein. The first step in this is to identify other parties interested.
Potential problems arise when engines use stemming.
Some agreement on the format of Centroids when they use stemming is going to be needed. There are significant research efforts already underway to explore the scaling issues associated with the use of centroids in query routing. We touched briefly on alternatives, but didn't go into any details. Below are two ideas which got over a sentence's worth of discussion. Feel free to scrap 'em.