PythonQt is a dynamic Python binding for the Qt framework. It offers an easy way to embed the Python scripting language into your C++ Qt applications. It makes heavy use of the QMetaObject system and thus requires Qt 4.x.
The focus of PythonQt is on embedding Python into an existing C++ application, not on writing the whole application completely in Python. If you want to write your whole application in Python, you should use PyQt or PySide instead.
If you are looking for a simple way to embed Python objects into your C++/Qt Application and to script parts of your application via Python, PythonQt is the way to go!