I don't think they're concerned about money at this point. Akin to the iTunes app store (1% of Apple's gross profit), they're not going to make a ton off of it

I don't think they're concerned about money at this point. Akin to the iTunes app store (1% of Apple's gross profit), they're not going to make a ton off of it all. What they probably want is a really awesome modding community surrounding their games that they control and are able to reward for efforts produced. Which is awesome in my mind.