this is a transcript from an interview some time ago :
Jonny Watts :
So, as we've already said; on the Q&A that John Laws did. Is that, we are interested in doing UGC the way you've said it; but it's not for release.
What I can tell you is that the game has been designed from the ground up to be ready for when we're ready to do that; or the way we load things into the game has all been designed to do that.
But for release, we really wanted to concentrate on doing what we call 'UGC in the box'
Which is slightly different. It's to give people ultimate creativity to a very fine level of granularity in the game.
So it's two stages. So to start off with, we want to give you the tools and all the things that our imagineers have made; which I think are incredibly beautiful.
And then once people have got tired of that, then we will start allowing people to model it in Maya or Max or whatever 3D Package they want.
But that's just a little bit later on after release.