> Interested in learning something that isn't PHP to code your web applications in?
That's the problem. I'm in the same boat as Marco with pretty much the same reasoning. I'm not interesting in learning something -- I'm interesting in starting and completing my next project as quickly, cheaply, and well designed as possible. I'm willing to accept that, all things being equal, a better design is possible in Python or Ruby. But for that to be true, I need to know Python or Ruby. I need to know the framework I'm working on.
I can certainly put the time into learning, the time into heading down the wrong path in both design and technology for a project (and that will happen), perhaps rewrite a few times. But with only so many hours in the day (less than I really need), it's not much of an option.