This is very possible to happent but the problem is the proportional conversion of ingame currency to Bitcoin.  We all know that ingame currency has no limit and can easily be acquired through selling, hacking and killing mobs.  And Bitcoin is limited to 21M coins, Maybe Bitcoin can be  use as payment to certain items and exchange of ingame currency to Bitcoin can be made.  The thing to consider, as what the earlier comment said is the exploitation of the sytem.  Possibly there will be lots of bot character ingame, making the game Bot infested and much less enjoyable for real players to play the game.