I willing to bet that modding will go on the decline years from now due to the simple fact that it takes much more effort and time to produce anything that's eye-catching or really deep in this day and age of demanding graphics and full powerhouse engines. All of a sudden, it takes months to model/texture weapons and simple objects, and it takes hours upon hours to make a detailed room look good. Really, the popular mods of these days literally have big "mod teams" to get anything done, so I can't imagine the effort it will take to produce anything significant upcoming years from now as one person when game development itself requires massive amount of work from hundreds of paid professionals. Although, by chance, maybe people will go "retro" and discover the fun of editing older games.
edit: Actually, come to think about it, it might not be so bad in the future. For example, engines like Crytek 2 come with a ingame level editor which would make things easier for average users.
Not really. Nothing really outside of Valve. The Source engine is already looking "outdated" if you compare the Orange Box games to other popular titles. Hell, it was showing its age when the first (released) version came out back with HL2. Fortunately people like Valve games, and if the developers used the same engine for Episode 3 despite what other current game engines offer now, I bet people won't mind too much. Something like the Unreal 3 engine is getting involved in licensing, not the Source no matter how much Gabe likes to stroke it.
You also have to consider that there are serious issues with the tools from the SDK for Source. As with new Valve games coming out, more and more technology is added to the engine and, the word is, the tools are simply not keeping up. I'm not judging from first hand experience, but I'm told of frustrations with how user-unfriendly editing with the Hammer is and how certain features of editing software would become broken when, let's say, new episodic content is released.
/rant?
SnailIracing:n(500tpostshpereline)pants
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