Serpent

Support for datatypes from the collections module from python's standard library, such as OrderedDict

register_class is now thread safe

Note: the rest of the serializer isn't and never will be - you still have to take care when serializing data that is also used in other threads

set_literals argument now defaults to True if the python version supports it (>=3.2), and False otherwise.

Android compatibility.

Option to add namespace/package prefix to class names in serialized data. Default=off.