Rails on Python?

Matt, if you want to have something Pythonic that is as comprehensive as Rails is, look at TurboGears. Look at version 2.0 that is currently is in beta. The documentation is incomplete, but it is rather usable already. It is built around Pylons providing a neat pre-configured package of everything you need to develop a good website. And if you don't like parts of it, you can replace parts of it with other things or even write your own parts.

Other people prefer Django, but it is too monolithic, non-modular and heavy to me.