The contest is open until it's closed and someone claims the prize! I think technically the Nyan Cat contest never got fully completed either so it's kind of still open too!
If you'd like to collaborate, get feedback, or otherwise have a reason to post your own [WIP] I'd suggest doing it over in Demos category. And then you can link to the post from here. Or just post in here.
If you finish the game by all means just post it up to Games category! We are very open minded here!