Pretty printing JSON will tend to make it heavier than those rendered without pretty print. Beyond that I can't think else of something between pretty printing or not.
Let's say you want to provide web services for a public RESTful Web API, will it affect server performance, round-trip time, etc.?
So again, what are the advantages and disadvantages of pretty printing JSON?
Advantages
Disadvantages
Thinking about this for all of 4 more seconds, I can't add any more to those lists! :P