Incremental work is great idea - I like this this style. Instead contrib, you can use public repository on github. Minimally for first stage is better to live outside core - you are not restricted by PostgreSQL development process. When your code will be stabilized, then you can go to commitfest. I believe so we need good JSON support. The XML support helps to PostgreSQL lot of, JSON will be great too.
Hi Pavel,
Thanks for the suggestion.
I am planning to use one of my own public github repos as the location for my work.
I thought by adding my first implementation to "contrib", we could make this functionality available to end-users, even before there was a consensus about what PG's "official" JSON-related operators should have for syntax and semantics.