The first community-driven update
You're into robots and Team Fortress 2, right? I knew there was a reason why I liked you. The latest major update to the game that will not end (and thank goodness for that!) is the Robotic Boogaloo Update, a one-hundred percent community-made initiative. It'll introduce 57 items that will be available from RoboCrates found either in the store, or as rare drops after June 3, 2013.
Could this be a hint of things to come? According to Valve, "This doesn't mark the end of Valve-produced TF2 updates, by the way. As far as we're concerned, there's plenty of room for both to happily co-exist. We're in uncharted territory here, and it's exciting to be exploring it with you."
If you're down with supporting user-made content, you'll also be pleased to hear that it won't merely be hat creators who benefit from this update. Valve says everyone involved has decided to share in the revenue generated from the sale of RoboCrate Keys.