Wing IDE
Wing IDE is written by Archaeopteryx. Even though it is brand new, it is clear that a lot of work and thought have gone into the design of this IDE. Wing IDE is a commercial application, and based on several open source components, like the great Scintilla editor component. But Archaeopteryx have already released parts of their work under an open source license. You can download a trial version of Wing IDE for free, and not-for-profit open source hackers can get a free license. If you use Wing to develop commercial products (whether open or closed source), you must buy a license for $99,00. I find this to be a reasonable attitude: After all, if you're going to earn money with a tool, you should pay for it.
I tested the first beta, which of course doesn't have the great stability of older products like IDLE or Pythonwin. In fact, when I tried to work on a reasonably large project using Wing IDE, I was faced by quite a few problems and crashes. However, the Archaeopteryx team was very helpful (even when they didn't yet know I was writing a review), and came around with bug fixes in a very, very short time.
The interface is a bit messy: There are a lot of windows open at the same time, making for a cluttered desktop, especially compared to Pythonwin. The toolbar icons are not really clear, and every window has the same set of icons, even though only a subset is applicable to each function.
Editor
The Wing IDE editor is the GTK port of Scintilla (see Figure 5). Scintilla is a very good editor in its own right, with great features like folding. It's pity that Wing IDE doesn't currently utilize all these features, especially folding, which can be very helpful. On the other hand, Wing IDE offers both calltips and autocompletion, and it appears that they've been far more successful in their attempt than others. Autoindent is not ideal: You have to press TAB for every line—but it indents to the right depth. There is no auto de-indent.
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Wing IDE's editor
Source Browsers
The Wing IDE source browser is simply fantastic (see Figure 6). Compared to it, all other Python source browsers are feeble. Not only does it show the structure of your code organized by file, hierarchy, or list of classes, but it also shows the doc strings, the arguments to every function, and even the code itself in a separate, editable pane. This is an extremely productive feature, because it enables you to quickly familiarize yourself with complex code.
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Wing IDE's transcendent source browser
I do have a quibble, though. The actual interface takes far more room than is necessary, due to the list of option boxes on the right-hand side. These could have been placed in the toolbar or in the menu, especially because it is very easy to obscure some options by dragging the separator bars.
Project Handling
Wing IDE offers a very serviceable project approach (see Figure 7). It is quite easy to import existing modules and Python files into a project, using a sensible selection box. In contrast with PythonWorks, Wing IDE does recognize that large projects can consist of several separate modules and can organize its projects accordingly. Because Wing IDE projects are defined in a project file that's stored wherever you want, you can use Wing together with RCS or CVS (or whatever you want), and this makes it suitable for large projects with more than one developer.
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Wing IDE's project manager
Debugger
The debugger offers a lot of functionality, but feels a bit slow (based on the first beta release) (see Figure 8). Running, single stepping, breakpoints—everything is present. Errors are reported in a separate window instead of jumping straight to the offending line in the source code, which is not really comfortable. The debugger is implemented as a separate server that can attach itself to any process. It's quite possible, for instance, to debug CGI scripts using Wing IDE. The second beta was quite a bit more snappy.
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Wing IDE's Debugger
GUI Handling
Wing IDE is based on one of the better GUI toolkits for Unix/X11 (although I feel that both PyQt and wxWindows would have been an even better choice, because they provide not only platform independence, but also a cleaner Python interface and are more stable). Despite this, it doesn't offer anything like a GUI designer. However, due to the open-ended nature of the Wing project definition files, it would be easy to include Qt Designer ui files, which can be translated to Python with pyuic.
Extras
There isn't a Python shell, but Wing IDE offers a lot of really powerful features that other IDEs don't have, like editor macros!