Between this and Sawdust, I'm seeing the beginning of a trend here...
What are you talking about, Don?
In all seriousness though, there have been plenty of circus-themed decks before Freakshow and Sawdust. Heck, there's already been a circus transformation deck.
I was referring to how these decks seem to come in cycles, like when there's suddenly a bunch of monster movies or killer insect movies coming out in a wave. We had a "black deck" wave, followed with "dark themes/skeletons", eventually we had a huge number of steampunk designs out all at once, and the current wave is zombies. I'm thinking that this could be the start of a new trend, where suddenly all at once there will be a handful of circus-themed decks coming out together.
A sure sign of a theme getting played out is when USPC releases an in-house version - at least in most cases. Look at the Alchemy/Anne Stokes decks, Bicycle Steam Punk decks in brass and silver, the Zombie deck, etc.
It's all speculation on my part, really...