According to Official Xbox Magazine, Valve said that they are discussing the possibility of porting over user made campaigns to the Xbox 360 version, made available through the Xbox Live Marketplace, even with possibly some of the money made from the maps being sent back to the original creator:
[Valve] wouldn't be able to give them away because "Xbox Live isn't set up like that," so it's considering distributing content and passing the money back to the creators.
"One of the things I'm thinking about is how we work within that [Xbox Live] system," said Valve's Yasser Mailaka, "and one of the things I'd like to do is to allow these modules that are being released on PC to somehow integrate with Microsoft's system."
"We'll have to filter them, we can't allow any copyrighted materials, so it's going to have to go through a process. But we're hoping perhaps we can shepherd the really popular campaigns onto 360. And you know, if they are a paid system, perhaps that could go back to the authors. I think that would be a great story."
All of which is great news for budding mappers, who if they do a good enough job could even be making money from the fruits of their labour. You can read the full article at Official Xbox Magazine.
(Via source-maps)