What is the quest-a-thon? Where can I find info about it?

It was an event a few weeks back where all users of the site tried to reach a certain number of quests done (I can't remember the exact number) and those that participated got a free pet slot

It was a week-long event last month. Everyone collectively did more than 500,000 quests so everyone who participated got a free pet slot and a title as a reward

Dang. Thanks for the info guys. I just missed it :(