Around Town After Hours
The well known secret of JavaOne is that the best stuff doesn't happen behind the doors of the presentation rooms at Moscone, but it happens in the restaurants, bars, and other meeting spots around Moscone. Sure, you can hear good things in the presentations, but it's the socializing with all those other attendees running around that you really find the benefits of coming to JavaOne. And that socializing continues on into the night.
Fun can even be found the night before JavaOne. For example, a few friends decided Monday night to do dinner. Those friends invited other friends and before you could say "Boo" there was barely a table big enough at Jillians (in the Metreon) to hold us all. Even though it started as just a group of friends, we ended up with a table full of people meeting each other for the first time. And great conversation ensued—despite the poor service of the overworked restaurant staff. (I recommend the Salmon. Yummy.)
After dinner, we headed over to XYZ ( the bar at the W Hotel) to hang out with the J2EE team. Drinks all around and lots of good conversation. The J2EE team was happy to have shipped J2EE 1.4 Beta 2 and were celebrating. I heard words like "exciting", "fast", and "groundbreaking" used to describe it. Mind you, I haven't used it yet, so I can't personally certify those comments, but I can say that the Kamikazes at the XYZ are quite stellar. And it was really fun to hang out with my old teammates.
So be sure to either get some rest in the morning, or take a nap in the afternoon. Sure the talks are good to go to, but you should really get out and about to truly enjoy JavaOne.