Warcraft3 is a multi-players game, I had used it's game editor before (just 3 months). In the editor, designer does not need to know which part is server/client, moreover, designer does not need any network knowledge. (The same as in editor of starcraft2)
Could we make a network plugin that any fool can use like the editor of warcraft3?
Well, I know browser can not be a server, so there is a big different between html5 with general socket application. So it's not easy...