They aren't a joke but, as garpu said, it still might be vaporware. They've a nice lil website with trailers of the proposed games that haven't worked for a while. All in all, I doubt their ability to produce a high quality, "best selling" PC game. Heck, even 12 year olds can (and do) code crappy PC games.

Still, I'm curious where they are gonna go with this idea and how they could pull off a bizarre Christian video game with killing/murder in the name of God. Talk about taking God's name in vain, Geez.