In his latest essay, Great Hackers, Paul Graham suggests that one mark of a great programmer is that, given the choice, they'll program in Python rather than Java. He points out that Google requires Python experience, even when hiring for Java positions, because it attracts better candidates.
Almost all of my "recreational" programming over the last five years has been in Python. I'm not saying that makes me one of Graham's Great Hackers, but it is certainly the case that, given the choice, I write in Python and not in Java. In fact, the only time I write in Java outside of work is when I'm writing plugins for Eclipse. The Eclipse platform is seductive enough that it keeps me writing GUI apps in Java, even when I have the choice.
The implication is, though, that if there were a Python equivalent of Eclipse (the platform, not just the IDE), I could cease to write in Java all together whenever I had the choice.
The first step would be getting something like wxPython to the level of SWT+JFace. Next would be a standard plugin framework.
The last couple of months I've wondered if Chandler might be the best avenue to achieve this. It already has a pluggable "parcel" framework and if it is going to compete as a PIM, it's going to have to drive wxPython to the level of SWT+JFace.
I still stand by my prediction about Eclipse being the next Emacs but I'd love to see a Python equivalent, whether it's Chandler or not.