Good luck, but you may want to reconsider. Andrew Godwin (author of South and Django contributor) is building a new version directly into Django core.

http://www.kickstarter.com/projects/andrewgodwin/schema-migr...

DevJoist is language agnostic so I think there will be a need for it regardless of what happens with Python. I'm actually a backer of Andrew's kickstarter :)

don't be discouraged. a solid, open-source solution that is language/platform agnostic is valuable.