Today the Milestone 2 of the VisualVM tool has been released. The most important thing about this release is that an experimental API has been defined for the third-party plugins to smoothly integrate into the UI and workflow. Currently only the Milestone 2 binary is available, the sources and API documentation will be available soon.
The other improvements in this release are separate threads view which is now available for each monitored application and basic support for VM coredumps on Solaris and Linux - displaying basic information and taking thread dump and heap dump from the coredump. Also some recent bugfixes of the NetBeans profiler have been merged into VisualVM.