I'm most interested in being constructive as well Fred, so let me make sure I got everything straight.
Arieg had created a user-sandbox page with his own version of Asura which was a WIP and yet to be submitted for approval. Wes then took that WIP version and merged it with the current official Asura article, but with his own inclusions. Arieg and Wes then went back and forward, editing, unediting and reverting each-other's work. Wes then made an In-Character forum announcement regarding his version of the article, making it 'official'.
If this is all correct, we need to address these problems so that they do not happen again before moving on. Otherwise, there is no point, as these things will keep on happening like it did with your own plot, and now this, setting us all back further and further each time. First, I believe Wes should apologize to Arieg before stating - very clearly - that he will not do so again. The reason for this is that not only are Wes' actions in this instance likely to be distasteful to new or prospective players, but also highly discouraging to preexisting players, as there is little or no motivation to produce any new content for the site if what they make can or will be arbitrarily taken and altered, as demonstrated by this event. I next suggest that, provided that any player interest in the plot or GM willpower to make it remains after these events, that Wes and Arieg work together to hammer out the details of the WIP-plot. Most importantly, Arieg needs to state very clearly what the intended end-result of the plot and its related meta-plot will be to Wes, as he is deeply concerned about Yamatai's well being.