When a form instance is returned from a view, it should return JSON

[sametmax]

Returning a form should be intercepted, and it should automatically return JSON with weither the form is valid or not, and errors.

If the form is unbound, it should raise an error

[sametmax]

Exemple of form to json serialisation: http://stackoverflow.com/questions/986406/returning-pure-django-form-errors-in-json