Arcade is an overall project. It is being worked on still. Zak is currently doing the global chat and workshop as his arcade API is mostly complete. However, there is a lot of work to do even when the API is done. Arcade is comparable to Casino - it is a very large feature.
So in the meantime, I am finishing up Fishing and starting on Zombie Massacre. Johanna is the only developer on Solar and it is very near to being released so it was pushed forward in our release schedule.
Fishing was moved forward because of the advances in the inventory stuff Foohy recently finished.
Full on development of Arcade will run our updates dry for months as it cannot be released in pieces and requires full focus. So to avoid that we are doing bits of it at a time.