It really all depends on the use case and your target end-points. JSON is great when the data is transmitted to and from web browsers because of JavaScript. Nea

It really all depends on the use case and your target end-points. JSON is great when the data is transmitted to and from web browsers because of JavaScript. Nearly every major framework has a really good XML library. Readability of the payload is usually not a concern, at least my experience, because only the software has to deal with it and not a human. Also in my experience the size difference between a JSON payload and an XML payload is not a big deal (except perhaps across slow network links where every byte counts, but there are more succinct and faster binary serialization formats available).