Coming from the embedded world, [http://www.osgi.org/ OSGi] is becoming hot in the desktop and server worlds as a micro-kernel that sits inbetween heavyweight application servers and lightweight containers.
The next version of [http://cocoon.apache.org Cocoon] will [http://wiki.apache.org/cocoon/osgi use OSGi] to manage hot-deployable application snippets, and the [http://directory.apache.org/ Directory project] is considering using it too. A proposal has also been made to the incubator to host the [http://oscar.objectweb.org/ Oscar] implementation.
Signup here if you're interested in getting together and talking more about OSGi, service management, and migration/integration strategies with existing containers (e.g. Avalon)
Thursday, 20:30, Room to be announced.