A public CPU miner is essential for launch to be considered valid in my opinion. Any coin instamined at a huge advantage by a small audience is doomed to fail.
I'm pretty sure that both CPU and GPU have been developed and I would be very surprised if the competition didn't include an optimised CPU miner - guess we'll find out tomorrow when entrants are released
I wouldn't be surprised if we see some early submissions with a whole host of updates leading into the final contest hours. My fear is that there will be a number of last–minute submissions on the eve of the contest closing.
Either way, if you know OpenCL or CUDA, you can probably land some easy money here.