While I have enjoyed each of the events I have attended at your facility and in the community, I have to disagree with you and state that while these happenings were plenty celebratory, they were not, in fact, spontaneous.
The Wake Up The Earth Festival, for instance, has been joyful to attend, but I must remind you that it was not in any way "performed or occurring without premeditation or external stimulus" or "preceding from natural feeling or native tendency without external constraint." While a lot of people who I encountered there might have benefited from a little less meditation, or maybe from paying a little more attention to their external stimuli, I still contend that this event on the whole just doesn't fit with these spontaneously googled definitions.
I have organized events in this city, and I know how much external constraint is required to get all those permits, and I know that the EMS and the police detail don't just show up out of people's native tendency (though too much showing of natural feeling could result in a patrol officer showing up). And all that advertising that I've been seeing for weeks now; it all has the same date and location on it. Clearly, this was planned.
You know what is spontaneous? Your staff updating your website. It's currently telling me the tentative date for the 2008 festival.
And for people planning to attend today's festival, be sure to take along some Festival Bingo Cards:
Download the .pdf of four different cards here. They should work at any Boston-area festival. Anything I left off? Let me know!