They've also explained, perhaps to justify the delay on releasing the CK, their work with Valve to integrate Steam Workshop into the Creation Kit:
Details on this are rather limited right now so there's no point in writing with too much conjecture. My hope is that the CK has not been delayed specifically to get this Steam Workshop functionality in. There's a crap-ton of bugs the modding community could be fixing right now with the CK, so I'd rather think positively and imagine they're spending their time to ensure the tutorials/wiki/support and CK are all as user-friendly as possible to promote as many people taking part as possible.
At the moment Steam Workshop is only available for TF2 and it has a relatively limited scope. As someone who hasn't used Steam Workshop and stopped playing TF2 a long time ago I can't speak from experience, but the "How it works" page on Valve's site states:
I'd assume this system will change for Skyrim else the scope for Steam Workshop and modding would be rather limited and wouldn't make full use of the integration with Skyrim and Steam. For example there are currently 3,500 files submitted to Steam Workshop for TF2 however only 40 items have been accepted for download (from what I understand of the system), so that's 1 in 87 files being accepted on to Steam Workshop. To relate that to TESNexus, of the 24,300 Oblivion mods available for download at a 1-in-87 chance of being accepted would mean there would be just under 280 mods available for download from Steam Workshop. As I said, details are scarce right now so we'll have to wait and see what sort of limits Steam Workshop will place on modding. I think it's pretty safe to say that some of the more risqué mods aren't going to be accepted to Steam Workshop, but who knows!
I'm glad Bethesda have at least made the system open so files can be shared and uploaded outside of Steam Workshop. It's early days but my worry is that by integrating the mods in to Steam we may well see an influx of pirates on the Nexus sites looking for mods that they can't get through Steam Workshop. We have never accepted piracy here and have banned thousands of accounts for openly admitting to piracy. We buy our games here and support Bethesda (and Bioware, CdProjekt, Trendy, etc.), and if you pirate your games and feel the need to tell us about it you won't remain on these sites. We do not want the Nexus sites to be a bastion of pirates looking for mods. Pirates, you have been warned.
I'd also like to take this time to say "I called it" to the mod authors here (I said I would!) who took part in our 26 page private discussion about bringing money in to the modding community. Mod authors making money from their work is a cool idea, but a massive game changer as well. The implications are pretty big for the community. Modding communities are built on the free sharing of information, knowledge, wisdom, assets and files. Will money affect that? I'll be talking more with mod authors about making licensing the mods you upload to the Nexus easier and more clear; last thing we want is people worrying that by uploading their files here someone else might try to profit off their hard work. This is, of course, if Bethesda are going the TF2 route with Steam Workshop.
The additional exposure that Steam Workshop will provide to the Skyrim modding scene will be great, I'm sure, and there are some great mods out there that will benefit from even more exposure and the ease-of-install Steam Workshop suggests it will provide. There are some very positive implications and some worrying implications, however there's no point worrying until we get more information. Needless to say both Valve and Bethesda have never been ones for trying to limit the creativity of their modding communities and I don't think that's going to change any time soon.
Interesting times ahead. Lets wait for more news and try not to go off on tangents without having the full facts.
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Update: A couple of people have tried to point out that talking about Steam Workshop opening up charging for mods at this stage is pointless since the Bethesda announcement clearly says "Using the Workshop, you’ll have free user content with the push of a button.". Perhaps I'm a bit more sceptical over press releases but suggesting you can get free user content does not mean there won't be paid for user content as well.
If the Apple App Store had a statement reading "Using the Apple App Store, you'll have free user content with the push of a button" they'd be right and wouldn't be lying. There are many free apps on the Apple App Store. There are even more paid apps. But the paid apps in the Apple App Store don't make that statement any less true.
I decided to send off a quick email to Matt Grandstaff, the Bethesda community manager, to ask him about the potential for mod authors to earn money through the Steam Workshop system:
Matt responded:
I tried to get a bit more clarification on this point as it still leaves a little room for interpretation (I want my clarifications ironclad!):
Matt has not provided further clarification on that point.
I hate to be sceptical about Bethesda when they've done so much for this community, but this still leaves me sceptical.