**Date**: 7th Dec 2012
* Serializers now properly support nullable Foreign Keys.
* Serializer validation now includes model field validation, such as uniqueness constraints.
* Support 'true' and 'false' string values for BooleanField.
* Added pickle support for serialized data.
* Support `source='dotted.notation'` style for nested serializers.
* Make `Request.user` settable.
* Bugfix: Fix `RegexField` to work with `BrowsableAPIRenderer`.