From PHP Everywhere today:

Ian Bicking has a very interesting and excellent Python blog. In Why Web Programming Matters Most he talks about PHP and Python:

And Python could have been PHP. We could have seen that kind of growth. But we didn't, because there has been and continues to be a bunch of little things that make Python annoying to use and get started with for web programming. But it's not all over -- PHP 5 is barely catching up to Python's features from 10 years ago. There's a lot of room for a better language to take it's place.

John makes a response to this statement, stating that it's the simplicity that people get confused with deficiency. They look at the features and wonder why PHP seems to be falling behind - when, in reality, there are still places where Python is lacking when compared to PHP.

So overall, I think that Python will never be as successful as PHP for web programming. Conversely PHP is weaker for general purpose work. And I think that is the way Python will continue to grow fastest: as a general purpose programming language, competing with Fortran, Java, C# and C++.