I have been using WingIDE for python program development for several years, and in general I am satisfied with it (esp. with their technical support). The learning curve for WingIDE was rather steep (at least for me). I am now considering some projects that I will require that I work with PyDev-Eclipse.
What kind of learning curve (steep -> easy, or not steep -> not easy) might one expect with PyDev?
I don't think there's a right answer here... Experiences vary a lot (I'd suggest following the Getting started tutorial http://pydev.org/manual_101_root.html and then judging for yourself... I think the basics should be easy to grasp, but as with anything else, to really master it will take more time, especially getting used to shortcuts and discovering what it's capable of).
I agree with Fabio that there is no simple answer. For Wing, start with the Tutorial in the Help menu. That takes you through the basics you need to know to work with Wing and use the debugger, and you can learn the other tools and capabilities more slowly over time.
The choice of IDE is as personal as choosing a keyboard. But for both the experiences of others sometimes help to make a choice.
In my case Wing has made the difference between advancing my Python skills relatively quickly, and some months of being bogged down by not understanding basic concepts. I have really found that the functionality Wing offers to go through existing code helps to understand Python and existing code more quickly.
With Pydev I got bogged down in the complexities of Eclipse. With Wing I felt that I was standing on the shoulders of people who grokked Python deeply. Note the word "felt", it is a very subjective thing, and you should most definitely take some time to try out what works for you.
Some things about Wing that make me believe it has helped me learn Python much more quickly than I would have otherwise: The Auto-Enter Invocation Args setting which shows up the PEP-8 way of invoking arguments to standard functions you are calling. And the go-to-definition and find-points-of-use functions that I have used many times to try to figure out how existing code works. This may all be available elsewhere, but it just works immediately and in a very coherent way in Wing.
