Personally I prefer Qt, but it really depends on what kind of user interfaces you want to make.
Against Win32:
low-level, high complexity to accomplish trivial things. You have to do EVERYTHING
if you go this route I would recomment a book like the one from Petzold.
Pro Qt:
Good looking GUIs
Can change the look and feel very easily by creating stylesheets
Signal and slots mechanism notifies you of UI events such as "button clicked" etc.
Nice layout system
Integrated with Visual Studio IDE
Modern object oriented c++ code, easy to understand and use
Qt Assistant (Very good documentation)
Relatively liberal licensing (LGPL)
Qt Designer - WYSIWYG design tool you can use for form design
Comes with a wealth of other c++ functionality including XML, networking, eventloops,
threading, database access, etc
Against Qt:
- Intermediary step of using MOC compiler
Pro WPF:
- if you want the new WPF capabilities of the new Windows platforms, WPF is the way to go.
