I wouldn't repost it here, you can read it at Doug's blog:
TL;DR: In summary, I talk a bit about:
- How it seems like the technical quality of Eclipse (the platform, and the JDT IDE) has not only failed to evolve but even declined a bit, more or less since the inception of the 4.x series.
- It also has not evolved much in terms of framework support for IDEs of other languages based on Eclipse (apart from the promising, but not yet very mature, DLTK project).
- Other IDEs are catching up (IntelliJ IDEA, MonoDevelop, even Netbeans), and becoming strong competitors.