I attended the DMG2-themed World Wide D&D Game Day today, at Gary's Game's in Seattle, Washington. A good time was had by all, though I had to leave early and didn't get to play in the second encounter.
The colloborative nature of the games was a blast. As the day was also International Talk Like a Pirate Day, the group I was in decided to give our adventure a bit of a pirate theme, with a piratical band of duergar pressing the young men of seaside villages into service and dark sacrifices - while an insane cleric of Tharzidun pulled the real strings.
Both groups decided that they wanted a "5-star, extra spicy" level of challenge, so the groups used a 2000 XP budget for each of the two encounters. That turned out to be more than enough for both groups. The group that faced our adventure was