I've found that I had to gradually replace large parts of web.py as my webapp evolved. For instance:

I had to drop the built-in DB library once I needed to connect to multiple databases. Global DB connections = bad. I suspect that if I'd kept using it, I would've had problems with transactions too.

I had to replace some of the request dispatching when I wanted to add code that triggers on every request (eg. logging, transactions, custom session management, "who's online?", traffic analytics).

I had to drop the Cheetah integration to add internationalization support - Cheetah supports the _ function, but only in precompiled templates.

I had to drop Cheetah entirely as the templates got a little more complicated and I wanted to factor some bits out. Web.py patches the Cheetah #include directive to do what you'd expect: include a file at compile-time (which is the same as runtime under web.py). With precompiled templates, however, it includes it at runtime, which means the included file can't have any #defs. Big pain.

It's not a bad framework to start out with, but you will end up needing to ditch nearly all of it by the time you've handled everything a typical webapp needs. If I were to do it over again, I'd probably start with Pylons. I'd consider Django, but I'm not sure you can swap out Django components the way you can with Pylons.

I use Python-Pylons/JS and Schevo for the backend. I have some experience with Django. Pylons is much better for serious programming - Django is better if you want to make a run of th e mill app like a blog. Using Pylons is like working with Lego bricks - stuff is swappable easily - not so with Django.

Yes, that's what I need and pretty much what webpy feels like to me.

If I were to switch to anything else, I'd probably try plyons first.

I really like webpy and its open ended approach, but Django is just a more complete framework, and thats what I need for rapid development. django.contrib contains user/auth and other things I'd need to roll my own in webpy. And the middleware, like session stuff - beeing written for django - ties nicely in with all the helpers (generic views, etc..), while still being loosely coupled. Initially I thought that Django was mainly for news driven sites, but I find it to be just as flexible as Rails and more explicit and intuitive. So basically I'm looking for the solution that allows me to write the minimum amount of code, while still providing the flexibility I need. And of course it has to be Python (because that's what I prefer).

I really appreciate these comments about webpy. I recently started using it and I love it for its simplicity, but at the same time I wondered about the advantages/disadvantages of its "anti-framework" philosophy against the full features of a mega framework ala Django, Pylons or TG.

I still find it very appealing, because 99% of the time, it is used for common, simple websites. And in these cases, its simplicity pays off. I like that I don't have to fiddle with multiple files or configurations, since everything can be contained in a single file in a very clear way, and just adding "web.run" to your script converts it into a running website.