It’s been almost three years that I first mentioned the NetBeans platform. The technology has since grown to be a first-class citizen in the NetBeans and Java worlds (with tooling support and books). The main difference with Eclipse RCP remains – NetBeans Platform is 100% Java/Swing.
VisualVM is a recent (and early) development based on the NetBeans Platform. It strikes an interesting balance between monitoring (a la JConsole), profiling (a la NetBeans Profiler, including a heap walker), and troubleshooting (new in Java 6). The platform is worth about half the application size, startup time is less than 5 seconds, and the application has a very professional look. The update center inherited from the platform isn’t functional just yet, but I can certainly see the value of this for future versions and plugins to extend the feature set.
If you’re in a Java 6 world, everything is really easy except maybe for profiling server-side applications which requires a fairly long time for the dynamic instrumentation to happen. Just like for JDK tools, VisualVM can also work on a remote process or a core file. More on VisualVM here.