I dont think it would be a good idea to make more campaigns but maybe more expansions that just requires one of the campaigns like EOTN.
my guess is that GW1 popularity will increase after GW2 is out because people will see what an awesome game it is and will wanna check out the original so sales of GW1 will most likely increase after GW2 is release.
I think Anet should not let GW die out after GW2 is out and should keep working on it and create more content this is such a great game and should be preserved for the future, who knows maybe they can release that unfinished Utopia expansion with all the money they will make when GW2 is out.
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