Wow, I checked this website earlier today and saw the beginnings of the thread. I wanted to post a response, but was reading it from my phone and didn't have time to do so at that point. I'm come back a few hours later, and bammm! the thread exploded. Clearly there are some very strong opinions here.
In my own experience of seeing a screenshot of diplo text for the first time, I too initially doubted whether it was within the rules and was frustrated by the effect the screenshot had on the course of the game. That said, none of the other players made an immediate issue of whether it was against the rules, so I assumed (probably the wrong decision since there is clearly a debate about it) that posting screenshots was an accepted practice and that I was just too much of a newbie to have experienced it before.
Regardless, I think there are two very distinct and legitimate questions here that should be separated.
1) Is it metagaming, as defined by the site rules, to use screenshots?
2) Even if it is not metagaming (therefore currently allowed within the rules), should screenshots (and more generally links) be allowed or banned going forward?
For the first question, I personally share Redhouse's interpretation of the rules and of course many other players disagree with that interpretation. We can argue about this all we want, but naturally the only interpretation of the rules that matters in the end is that of the mods/admins/owner. Based on Abdemacht's post, it seems like it has been ruled as not-metagaming. I disagree with this, but am not in a position to question that decision. That said, I think the rules as they are written are vague and clearly led to strongly divergent interpretations, so I would hope that they could be made more clear.
For the second question, I believe strongly that screenshots should not be allowed going forward (regardless of their use in the past), even if they are not metagaming. I agree with Redhouse that allowing screenshots moves this site in a direction that in my opinion is not desirable.
Before reading this thread I did not know how easy it was to forge a screenshot. I figured you had to use Photoshop. Because of the attention this has received, other players will now all know this and will suspect the authenticity of all screenshots they receive, just as they already do with cut/pasted text. But what then?
As others have noted, you could simply use a webcam and send a link to a video rather than a picture, which we all agree would be much harder and require much more advanced technical skill to forge. As long as you do this in a way that preserves anonymity during anonymous games, it seems that this would be a natural option within the current rules that players would inevitably pursue to try to find advantage in the game. I'm personally no good at technical stuff and wouldn't want to dedicate the time or effort to learning how to forge a picture, let alone a video. When I play Diplomacy, I want the result to be decided by my skill at diplomacy, strategy, and tactics, compared with the other players in the game. Just as Redhouse said earlier, I do not want my technical computer skills to be relevant to my success or failure.
All of that said, I absolutely respect the views of others in this thread that screenshots can be used as just another tool of deception, just like using audio-recording equipment in FtF. This is a game, and more relevantly a simulation of diplomacy and Great Power politics. Everyone is entitled to their opinion about what should be allowed or not allowed in that simulation provided that all playing understand and agree to it. If you are playing FtF and all agree that it is fine to use audio equipment, steal orders from the box when no one is looking to read/alter them, allow other players to submit orders on your behalf, etc. than that is fine as long as you're not breaking an actual law. The more things you allow, the more the simulation moves towards the real world of politics, diplomacy, etc, and this could legitimately enhance or detract from a particular players enjoyment of the game. Wanting to make your technical skills computer relevant to your success in the game is a valid viewpoint and certainly brings the simulation closer to reality. In my own opinion though, if I wanted the simulation of Diplomacy to be that close to the reality of diplomacy I'd just choose to focus my time on the real world stage rather than in the game.
From what I learned from previous posters, it is now clear to me that it is easy to forge a screenshot and that therefore this provides nothing beyond what is already provided by cutting and pasting. Allowing links to pictures however opens the door to allowing links to video. I believe we should just leave it at cutting and pasting and decide that opening the door to linking to pictures and video would only raise the relevance of technical computer skills and take this community in a direction we don't want to go.
Of course we all play on the same site and all need to play under the same rules (with some variations allowed under certain pre-approved contexts). As a community we should discuss this issue and then yield to the decisions of the mods/admins/owner. I am just one humble voice against allowing this to continue and snowball in what I think would be an undesirable direction.