Eclipse 3.0 is available for download from the 25th of June. I downloaded and installed it. It looks great and has some great new features, among others integration with JUnit.
However, after pointing Eclipse 3.0 to your Eclipse 2.1.x workspace, Eclipse 2.1.x doesn’t like the workspace anymore. In particular, the classpath of the projects were damaged. So make a backup of your workspace before trying 3.0 and then switching back to 2.1.x.
I’m still waiting for the Lomboz plugin for 3.0 to become available. Thereafter I’ll switch to 3.0.