We just finished migrating the database for our Django 1.6 app from MySQL to PostgreSQL. If you have a clean environment this process is as simple as running syncdb and/or migrate to create the tables, truncating the data in those tables, and running the dumpdata and loaddata management commands.
Here are the steps to do this:
Step 1: Create an empty database in your PostgreSQL instance
CREATE DATABASE dbname OWNER rolename;