What I learned at Java One:

Twitter- a great way to locate the best parties

Open source - If you have a brand name company donate software to your project you generate A LOT of interest (Ericsson and GlassFish). And in case you missed it Portal 7.1 announced it was open source.

Parties- The best one I attended was the open source unBOF @ the Thirsty Bear (best because of the people (Geir being pinned to a dart board by Juggy - video in production) and the great conversations and the minimalist(read recruiting party) was Google.

Open Source Panel - Simon's salon on open source was well attended with lots of dicussion about licenses which was a prelude to Microsoft's big announcement to extend full employment to more lawyers