Apple Support for Eclipse
Apple Developer Connection had a booth at EclipseCon last week, and are showing signs of support for Eclipse with an article posted just in time for the conference. The article, "Developing Java Applications on Mac OS X with Eclipse" also serves as a nice introduction to Eclipse for non-Mac users.
The Apple personnel were openly stating that they are planning to hire an SWT software engineer. This new employee could enhance compatibility between SWT, the Eclipse platform, and the Mac (I've had good results with it already). A member of the Eclipse SWT team told me that Apple did not yet have a committer for the SWT project, but that they could easily get started by offering patches.
Even though Apple has their own X-Code IDE and Objective-C language, they are doing a great job of supporting developers in a wide variety of languages and tools for developing OS-X or cross-platform apps. For example, at OSCON last year, Guido van Rossum mentioned that Apple worked to make sure that the latest version of Python shipped with OS 10.3 "Panther". Apple is previewing J2SE 5.0 for the upcoming OS 10.4 "Tiger".
There were a good number of Apple laptops at EclipseCon, but corporations are still purchasing Windows laptops in bulk for their employees (and of course, IBM had a strong presence with lots of ThinkPads). From the laptops seen at last summer's OSCON, Mac has developed a huge following in the open source community.