Here are a few Python language features that I seriously miss when I'm working in PHP:
- Modules and namespaces! This is the feature that initially drove me away from PHP.
- List comprehensions (let you construct a new list based on an old list in a one-liner)
- Built in iterator support (easy "for item in collection" support for many different types of collection)
- First class functions and closures (so you can treat your functions as data)
Those are just four off the top of my head. If you haven't looked at Python before (but already know how to program) I suggest taking a look at http://diveintopython.org/ which is a free online book.
Namespace support in PHP never really bothered me, but I've occasionally run into problems with name clashes with built in functions. It'll be welcomed anyway for sure.
Python is a very good language: easy to learn, powerful and fast enough (provided you understand how to make its various frameworks scale).