I wanted to post the Disney Parks info-page on the volunteer promo: http://disneyparks.disney.go.com/disneyparks/en_US/WhatWillYouCelebrate/index?name=Give-A-Day-Get-A-Disney-Day
I also just saw this cool thing at Theme Park Insider -- if anyone is in or near Orlando in December, this Habitat for Humanity build might be fun! This won't count for the promo, but it's still a neat idea. http://www.themeparkinsider.com/flume/200910/1479/
I'm considering getting a bunch of friends together to volunteer in my community for the promo -- could make a whole day out of it. Meet in the morning with donuts and coffee, spend the day volunteering, then head back to someone's house for pizza and game night!