Just wanted to anecdotally affirm whalesalad's experiences with my own. I desperately wanted to like Django more than Rails (I just really appreciate python as a language), but I find projects much quicker to build in Rails. It really is the convention-over-configuration magic that makes the difference. There's less to do in Rails to add commonly used web/crud functionality - but it's much less explicit and relies on you getting all the conventions correct. Rails is really the only framework that I've found fairly hard to learn, simply because you have to memorize the conventions to know e.g. where to pluralize and what magic helper methods will have been auto-generated.
It should be noted I've never worked on a large Django project - I suspect once a site's data structure and main functionality has been nailed down and you get a larger team involved, Python and Django's 'explicit is better than implicit' design philosophy will start to provide increases in efficiency.
I feel like you can tell a good rails developer by finding who thought it was hard to learn. There really is a lot you need to know under the magic, and if you can learn to create compatible magic in your own code the framework becomes incredibly extensible.
My Rails projects have always been the ones that felt the most done on their initial release. That extra time not typing and configuring goes into caching, validation, UX, and making nice solutions to project specific problems that fit nicely and don't become pain points as time goes on. All these things that can feel shortchanged in other projects get more of the polish they need sooner.
I've worked on a handful of large to very-large Rails apps, and I find that after a certain level of size, you're dealing with a Ruby code base that happens to have Rails as the way it is presented. Rails' implicit functions are either obvious because you use them often, or just not relevant, since you're deep in plain Ruby objects implementing your business logic.