Have you looked at this?
http://www.phpbuilder.com/columns/chow20040921.php3
I've been spending some time trying to learn it; I've never coded on anything more complex than a color-coded, line numbered text editor, but I'm convinced that if I can get a grip on the concept that it will be well worth the effort of making such a major shift in my practices.
I just added the subversion plugin to it; I was originally looking at it in view of a C#-.NET job offer that I got (they use MS exclusively, I was looking into being able to work at home using Mono on my Mac), and it has plugins for just about anything you can imagine, and a few you can't (even a games plugin!) It's really rather impressive.
As a J2EE developer for the past 6 years, I've used some great IDE's, the best of which was IntelliJ from JetBrains. It was like Dreamweaver for enterprise Java development, and it knew more about my code that I ever did... During my last contract, I was forced to use Eclipse and after release 3.0, it finally caught up enough with some of the features of IntelliJ that I switched (though until now, there were never any decent JSP plugins, so I kept IntelliJ on the desktop).
I've considered using different PHP plugins with Eclipse, but honestly, I couldn't find the right combination of free plugins that gave me the web development features of Dreamweaver, despite the fact that it has great potential in XHTML, CSS, PHP, JavaScript, and just about any other editing capabilities you can think of.
Now, some of the commercial plugins are to-die for. I used an XML/XSLT plugin that made light work of the complex XSLT based exports I was managing for a major American networking company for the past two years. Generally, the free ones were nice, but didn't have sufficient features to be a viable Dreamweaver replacement.
I may start looking around again to see if this, or any other free (or inexpensive) plugins are providing a fully integrated PHP web development environment, and if so, I'll crank it up again and we can do all sorts of great things together with it. It's the bomb in Java, but not convinced it's the best choice for web development, yet...