I have recently had a conversation with a friend of mine whom used to play the old MUDS, and he noted that with the release of guild wars 2, you won't be selling many copies of the original guild wars campaigns. here's his idea: release tools to create content for guild wars. this idea may not seem that good until you consider the possibilities; 1, sell the tools for 15 to 50 dollars in order gain from it. 2, you won't have to host the information; each campaign a person creates will be a single-player deal, all the info is hosted on his computer and it can be accessed from the guild wars client (shifts into a non-online mode). 3, every year or so, you can host a contest that will find the best, most skillfully designed campaign and allow it to go online (you won't have to add it to PVP and you won't be able to use the user developed skills in other campaigns) and sell the game for the price of a normal campaign. there are multiple advantages to introducing these tools; 1, this will attract the modding community. 2, modders will need to buy the full game and the mod tools to use thus generating revenue. 3, it won't cost you extra money for servers except for once a year or so because people can share they're campaigns via the internet or burned DVDs, on the contrary, it will make you money because people will want to play the runner-ups so they buy the game. 4, free labor! 5, this will extend the life of guild wars for years.

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EDIT:
you could also sell spots on severs to make the content public for you're guild, or you could allow them to host they're own campaign

campaign needn't interfere with the canon because the could be on another continent.

this could allow you to create expansions for guild wars 2 based on the winning stories

you could have people pay 100 or so dollars to make campaigns available online that haven't won a contest (these would be sold cheaply and must pass quality control)

lower mod tool price to free or $5
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