The Glassfish Unconference was a kind of "openspace" - all participants gathered together at round-tables and exchanged experiences / requests / problems in areas like: Scripting, Java EE 5, Production/Performance Tuning/Monitoring, Clustering etc. It was small, nice and intense. There was a lot of opportunity to talk directly with committers, product owners etc. The party afterwards was even better. I discussed with Netbeans/Glassfish engineers some ideas and issues. I really enjoyed the talks - these guys were really open for feedback and requests (at least I had the impression).
The breaking news: Glassfish v3 is based on OSGi now - HK2 seems to be dead - it was announced at the last year JavaONE :-). The interesting story is: what happens in case JSR-277 will come? HK2 aimed to provide a lean abstraction layer between Glassfish modules and OSGi / Java Module System.
Online workshop: Java EE 7 Bootstrap