I imagin it will do no worse then LotR. It will be there for ex-wow players, but wont replace wow.
Remember, WoW actually pulled people from eq in beta. Many people incl me (Who was a progressing raid player in eq) thought it was the best thing since sliced bread, and that was while it was still in beta. I game has to pretty much be awesome in beta to top wow, this wasnt it. Maybe next time. Saddly guild wars 2 is still aways down the line.
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