It certainly wasn't easy. Although the vast majority of the difficulty can be attributed to porting application code, some difficulty can be attributed to Django. I would have preferred a framework which makes it easier to swap out components, but it is unclear how much it would have really mattered except for in terms of psychology.
Well, this is something I've been quietly agitating about for a while, because I have a feeling that your case is one where "swappability" doesn't help much -- once you've written your application code around a particular component, switching to another component is going to involve rewriting. How much rewriting may vary, but AFAIK there's nothing that can automagically port code, say, between popular Python ORMs.
