The other article I read said that Ceglia paid Zuckerberg $1000 to create thefacebook.com. Ceglia owns a car dealership or something and was also trying to reach out into social networking (investment opportunities I guess). The initial contract was that Ceglia would maintain 50% ownership, and Zuckerberg would lose 1% for every day the project was late. Basically, Ceglia was an initial investor into thefacebook, which Zuckerberg later transitioned the idea to plain-old facebook. That's how I understand the situation.
If this man initially paid Zucks $1000 for 50% of facebook, that's where it stands. If this guy wins, all of facebook's subsequent investors are going to have a nice lawsuit to file against Zuckerberg.
Face it, Zuckerberg's a tool. He probably thought he could get out of the deal by moving to a different domain name. The guy has shown over and over that he has no idea how to run a company.