Free Engines And The Future Of Modding?

When Unity 3D went free a friend of mine started playing around with it and voiced the opinion that mods would now increasingly become free or indie games, because here was a 3D engine that was so easy to use, and so straightforward to port assets into. Then we had the UDK announcement, which gave us modder's favourite, the Unreal Engine, as a free platform. So what does that mean for the future of modding?

I'd always presumed that modding was so popular because it was a shortcut to professional-grade 3D engines. It was a step-ladder, a short-cut, not only to the technology but also to the tools needed to make use of it. Now, however, we have a situation where those engines are not only free to use, but also stand alone: you won't need your players to own an Unreal game to play something made with UDK. With open stuff like Ogre, and free stuff like Unity, we now have an embarrassment of 3D engine riches, and it seems to me that modding teams will indeed stretch their ambitions that bit further to move their activities over to these engines, and own their work. Crucially, their efforts no longer need be confined to particular communities: they can make games in UDK and anyone will be able to play them.

So what does that mean for modding? What fraction of the current modding community would or could step away from their parent games and develop for these platforms? And would that end the likelihood of there being another Counter-Strike or Killing Floor? Why would the talented few sink their time into yet another mod, when they could be aiming for their own indie game using a free engine?

Modding has already seen something of a decline as engines have become more difficult to work with - the thing Carmack was talking about with the difficulty of introducing new tech to modders and amateur designers. Combine this with games increasingly closing off areas in which modders could work - as in the case of MW2 - and are we at the end of the great modding arc?

Of course I expect that as long as the PC exists we'll get tweaks and alterations for existing games - those compilations of alterations and unlocks that make Stalker so complete, for example, or the balances generated by the community for Total War games - but what of the most vital life-blood of the modded games: the total conversions and remakes? What modding has done best is generate those impressive titles that occasionally break through the meniscus of amateur ambition and into commercial production. Titles that inspire commercial development. Will modders not now move their ambitions on to these new 3D engines? And will that be for the good, or the detriment, of the PC as a gaming platform?

I'm asking you, Internet, because I really don't know, and I think the question needs to be asked.