That what I want to know, too.
IntelliSense? ActiveState Komodo does this. And it does it very well considering the potential complexity of trying to determine what identifiers are possibly valid in a dynamic language.
Debugger? No thanks. I haven't used it yet. [I should probably blog on the perils of debuggers.]
Project Management? GitHub seems to be it. Some IDE integration might be helpful, but the three common command-line operations -- git pull, git commit, and git push -- seem to cover an awful lot of bases.
I've been asked about Python IDEs -- more than once -- and my answer remains the same:
The IDE Doesn't Matter.
One of the more shocking tech decisions I've seen is the development manager who bragged on the benefits of VB. The entire benefit was this: Visual Studio made the otherwise awful VB language acceptable.
The Visual Studio IDE was great. And it made up for the awful language.
The development manager went to to claim that until Eclipse had all the features of Visual Studio, they were sure that Java was not usable. To them, the IDE was the only decision criteria. As though code somehow doesn't have a long tail of support, analysis, and reverse engineering.