In the end, until the virtual universe agrees on common currencies the system is useless long term. As new virtual worlds are born and others die (sometimes in the matter of a couple years) the currencies become lost in time. So the general public never learns of or attributes any real value to the virtual currencies.
btw, is this really any different than 10 years ago where people were selling and buying Blizzard's Diablo items for real cash?
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