The Spohn challenge is relatively simple. Write one new short story per week for a whole year. It can be serialized or it can be anything you want it to be. Check out the details of the challenge here.
That being said, I'm not sure if I will make it a post a week - I'd like to, but hard to say, but I will definitely give this a try. When I get the first one done, I'll add a writing challenge tab to my navigation.
If you plan on joining the challenge, be sure to leave a reply here or on Steven's page.