PyGreSQL vs psycopg2
Licensing may be an issue for you. PyGreSQL is MIT license. Psycopg2 is GPL license.
(as long as you are accessing psycopg2 in normal ways from Python, with no internal API, and no direct C calls, this shouldn't cause you any headaches, and you can release your code under whatever license you like - but I am not a lawyer).
What is the difference between these two apis?
Which one faster, reliable using Python DB API?
Upd:
I see two psql drivers for Django. The first one is psycopg2.
What is the second one? pygresql?