I hear the saying "JavaONE is only good for socializing" over and over again. This is exactly *not* my experience. You get the unique opportunity to talk to Sun engineers and get your questions answered. During the last JavaONE I had some nice and informative conversations with the core HotSpot, Glassfish, openSSO, and Java FX team. I had to sacrifice the After Dark for that purpose - but it was really worth.
BOFs are especially valuable for deep technical conversations and get your questions answered. But even the Glassfish Unconference and CommunityOne were interesting. I got some Hadoop, Google App Engine, Hudson, IceFaces, JavaFX and openSSO questions answered - directly from the committers. It saved me probably days, if not weeks, of research.
From my perspective JavaONE is absolutely worthless for socializing - it is too much interesting stuff going on :-). I try every year to spend more time at the pavilion, but I couldn't manage that. This was also the reason, why I scheduled my podcast at the very last - it was hard to find other free slots.
I actually only used the breakfast for socializing - few minutes a day :-). Lunch was already problematic - there were some interesting, technical sessions during the lunch as well.
This year I even didn't used my notebook during the sessions (except some general sessions) and entirely concentrated on the content and asked questions - this really paid off. JavaONE from my perspective is 12h / day technical content with 1% opportunity to spend time on parties :-). You need vacations after that event for sure - and probably some time for socializing :-).