Django 1.5 : Python 2.7 or Python 3
If I was starting a new development which I didn't expect to go live until well after version 1.6 is released (when Python 3 support is supposed to be production ready, and hopefully the 3rd party apps have caught up) , then yes, I would go with Python 3. It is significantly cleaner than Python 2.7.
But if you want your site up and running in the near future, stick with 2.7.
Django just release their 1.5 version. 
It now supports Python 3, my question is quite simple indeed: With this 1.5 Version, should I still use Python 2.7 or Python 3 ? I assume that with Python 3 there will be some issues with 3rd parties app no ?
In your case, what would you do ?