If you don't own the game, any downloaded rom^H^H^H map has to be removed within 24hrs of downloading from your hard drive!
No but seriously, we're not going to give time frames or anything on that. I doubt in 10 years we're going to care that much, being modders ourselves and all.
But think about it, would you want your game to be picked apart and your hard work that you've spent more than 4 years on to be slapped in to unrelated doom/duke mods without any compensation? Including assets like that could even be viewed as a subset of piracy but let's not go there.
I'm all for sharing and such but we're talking about a game that we've invested quite a bit of our own salary and a huge amount of time and dedication; i.e. I just spent a month of "vacation" from work, practically locked inside working 12hrs days just to get progress the game and I'm not alone in the team. This is not to summon a violin in to this conversation but just to tell that this stuff is way past a freebie
I think we can do better than Nintendo or various Duke/etc.. projects that have been killed over the years but this is way too early to tell.
People are more than welcome to use assets in a way that requires a legal copy of the full game. This can be done with installers/patchers and whatnot.
We will fully support creating mods against IM and of course and we do not plan making any of the asset usage harder, except for the current previews to exactly mitigate asset ripping before we even get a chance to show them ourselves proper. Bottom line: We just don't believe the near future is the time to give those away for free.