As soon as Android head Sundar Pichai tweeted the image of a KitKat-themed Android statue on the lawn at Google, it was on. The official KitKat twitter account got in on the fun, and the Android KitKat website went live with a confirmation that it was indeed going to be Android KitKat. What's more, this is not Android 5.0. This is 4.4.
The Android KitKat site has a neat little retrospective of the entire Android version history and a bit of info about a contest.