What problems may using the MIME type application/json cause?

Question

I am working on a web service the needs to return JSON data. I read that I should use application/json but am not sure what problems this may cause?

For example, w

Answer 1

This has been discussed before:

What is the correct JSON content type?

Any firewalls that block the MIME type will cause problems with any AJAX-style web apps, so I really wouldn't worry about it.