People around the world danced the quirky zombie choreography of the "Thriller" video, and came dressed as zombies and Michael Jackson -- which could be the same thing, seeing as an animated Jackson at this point would be undead.
"Thrill the World" sought to have a total of 200,000 people demonstrate the soul of "getting down". About 200 of them showed up in Broomfield, Colorado.
This is actually not the only dead festivities in the Frontrange area of Colorado. There is also Frozen Dead Guy Days and the Zombie Crawl.